If the joint probability density of X and Y is given by Find a) Marginal density of X b) Conditional density of Y given that X-1/4 c) P(Y < 1/X = ¹) d) E (YX =) and Var(Y)X = ¹) e) P(Y < 1|X<=) f) Let X and Y have a bivariate Normal distribution with X-N(70,100) respectively, and p = 5/13. Evaluate P(Y S841X= 72). [ 14 marks] (2x+y) for 0

The probability that the female student’s commuting time is less than 50 minutes is 0.645.

The computation is as follows:Let X be the commuting time of the female student. Then X ~ N (μ = 46.3, σ = 7.7)P (X < 50) = P [Z < (50 - 46.3) / 7.7] = P (Z < 0.48) = 0.645where Z is the standard normal random variable.To find the probability her commuting time is less than 50 minutes, we used the normal distribution function and the standard normal random variable. Therefore, the answer is 0.645.

We are given the mean and standard deviation of a certain female student’s commuting time to SCSU. The commuting time is assumed to be Normally Distributed. We are tasked to find the probability that her commuting time is less than 50 minutes.To solve this problem, we need to use the Normal Distribution Function and the Standard Normal Random Variable. Let X be the commuting time of the female student. Then X ~ N (μ = 46.3, σ = 7.7). Since we know that the distribution is normal, we can use the z-score formula to find the probability required. That is,P (X < 50) = P [Z < (50 - 46.3) / 7.7]where Z is the standard normal random variable. Evaluating the expression we have:P (X < 50) = P (Z < 0.48)Using a standard normal distribution table, we can find that the probability of Z being less than 0.48 is 0.645. Hence,P (X < 50) = 0.645Therefore, the probability that the female student’s commuting time is less than 50 minutes is 0.645.

The probability that the female student’s commuting time is less than 50 minutes is 0.645. The computation was done using the Normal Distribution Function and the Standard Normal Random Variable. Since the distribution was assumed to be normal, we used the z-score formula to find the probability required.

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The probability of a certain female student's commuting time being less than 40 minutes is 0.205.

The probability of a certain female student's commuting time being less than 40 minutes is required to be found. Here, the commuting time follows a normal distribution with a mean of 46.3 minutes and a standard deviation of 7.7 minutes, given as, Mean = μ = 46.3 minutes Standard Deviation = σ = 7.7 minutes

Let's find the z-score for the given value of the commuting time using the formula for z-score, z = (x - μ) / σz = (40 - 46.3) / 7.7z = -0.818The area under the standard normal distribution curve that corresponds to the z-score of -0.818 can be found from the standard normal distribution table. From the table, the area is 0.2057.Thus, the probability of a certain female student's commuting time being less than 40 minutes is 0.205.

Thus, the probability of a certain female student's commuting time being less than 40 minutes is 0.2057.

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The probability density function (PDF) of XI, the lifetime of a certain type of device, is defined as follows:

f(x) = 0, if x ≤ 21

f(x) = 1/21, if x > 21

This means that for any value of x less than or equal to 21, the PDF is zero, indicating that the device cannot have a lifetime less than or equal to 21 months.

For values of x greater than 21, the PDF is 1/21, indicating that the device has a constant probability of 1/21 per month of surviving beyond 21 months.

In other words, the device has a deterministic lifetime of 21 months or less, and after 21 months, it has a constant probability per month of continuing to operate.

It's important to note that this PDF represents a simplified model and may not accurately reflect the actual behavior of the device in real-world scenarios.

It assumes that the device either fails before or exactly at 21 months, or it continues to operate indefinitely with a constant probability of failure per month.

To calculate probabilities or expected values related to the lifetime of the device, additional information or assumptions would be needed, such as the desired time interval or specific events of interest.

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The average selling price of a smartphone is estimated to be $318 with a 90% confidence interval.

a. Constructing a 90% confidence interval requires calculating the margin of error, which is obtained by multiplying the critical value (obtained from the t-distribution for the desired confidence level and degrees of freedom) with the standard error.

The standard error is calculated by dividing the population standard deviation by the square root of the sample size. With the given information, the margin of error can be determined, and by adding and subtracting it from the sample mean, the confidence interval can be constructed.

b. To calculate the margin of error, we use the formula: Margin of error = Critical value * Standard error. The critical value for a 90% confidence level and a sample size of 31 can be obtained from the t-distribution table. Multiplying the critical value with the standard error (which is the population standard deviation / square root of the sample size) will give us the margin of error. Adding and subtracting the margin of error to the sample mean will give us the lower and upper limits of the confidence interval, respectively.

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The correct Question is: The average selling price of a smartphone purchased by a random sample of 31 customers was $318, assuming the population standard deviation was $30. a. Construct a 90% confidence interval to estimate the average selling price.

We have to find the values of x for which the given series converges. Then we will find the sum of the series for those values of x. The given series is as follows: the values of x for which the series converges are -3 < x ≤ -1 and the sum of the series for those values of x is given by -(x + 2)/(x + 1).

Sigma n=1 to infinity (x + 2)^n

To test the convergence of this series, we will use the ratio test.

Ratio test:If L is the limit of |a(n+1)/a(n)| as n approaches infinity, then:

If L < 1, then the series converges absolutely.

If L > 1, then the series diverges.If L = 1, then the test is inconclusive.

We will apply the ratio test to our series:

Limit of [(x + 2)^(n + 1)/(x + 2)^n] as n approaches infinity: (x + 2)/(x + 2) = 1

Therefore, the ratio test is inconclusive.

Now we have to check for which values of x, the series converges. If x = -3, then the series becomes

Sigma n=1 to infinity (-1)^nwhich is an alternating series that converges by the Alternating Series Test. If x < -3, then the series diverges by the Divergence Test.If x > -1,

then the series diverges by the Divergence Test.

If -3 < x ≤ -1, then the series converges by the Geometric Series Test.

Using this test, we get the sum of the series for this interval as follows: S = a/(1 - r)where a

= first term and r = common ratio The first term of the series is a = (x + 2)T

he common ratio of the series is r = (x + 2)The series can be written asSigma n=1 to infinity a(r)^(n-1) = (x + 2) / (1 - (x + 2)) = (x + 2) / (-x - 1)

Therefore, the sum of the series for -3 < x ≤ -1 is -(x + 2)/(x + 1)

Thus, the values of x for which the series converges are -3 < x ≤ -1 and the sum of the series for those values of x is given by -(x + 2)/(x + 1).

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The missing value required to complete the probability distribution is 2, and the standard deviation for the given probability distribution is approximately 1.034. This means that the data points in the distribution have an average deviation from the mean of approximately 1.034 units.

To determine the missing value and calculate the standard deviation for the probability distribution, we need to determine the probability for the missing value.

Let's denote the missing probability as P(2). Since the sum of all probabilities in a probability distribution should equal 1, we can calculate the missing probability:

P(0) + P(1) + P(2) = 0.07 + 0.2 + P(2) = 1

Solving for P(2):

0.27 + P(2) = 1

P(2) = 1 - 0.27

P(2) = 0.73

Now we have the complete probability distribution:

x  |  P(x)

---------

0  |  0.07

1  |  0.2

2  |  0.73

To compute the standard deviation, we need to calculate the variance first. The variance is given by the formula:

Var(X) = Σ(x - μ)² * P(x)

Where Σ represents the sum, x is the value, μ is the mean, and P(x) is the probability.

The mean (expected value) can be calculated as:

μ = Σ(x * P(x))

μ = (0 * 0.07) + (1 * 0.2) + (2 * 0.73) = 1.46

Using this mean, we can calculate the variance:

Var(X) = (0 - 1.46)² * 0.07 + (1 - 1.46)² * 0.2 + (2 - 1.46)² * 0.73

Var(X) = 1.0706

Finally, the standard deviation (σ) is the square root of the variance:

σ = √Var(X) = √1.0706 ≈ 1.034 (rounded to the nearest hundredth)

Therefore, the missing value to complete the probability distribution is 2, and the standard deviation is approximately 1.034.

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The mean number of batteries sold over the weekend calculated using the mean formula is 4.56

Outcome (X) | Probability (P(X))

2 | 0.20

4 | 0.40

6 | 0.32

8 | 0.08

Mean = (2 * 0.20) + (4 * 0.40) + (6 * 0.32) + (8 * 0.08)

= 0.40 + 1.60 + 1.92 + 0.64

= 4.56

Therefore, the mean number of batteries sold over the weekend at the convenience store is 4.56.

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The value of cosecθ is the reciprocal of sinθ.cosecθ = 1/sinθcosecθ = 1/3√55.The required values aresecθ = 8/√55,cotθ = 3/√55,cosecθ = 1/3√55.

Given a triangle with sides 8, A, and 3.Using Pythagoras Theorem,A² + B² = C²Here, A

= ? and C

= 8 and B

= 3.A² + 3²

= 8²A² + 9

= 64A²

= 64 - 9A²

= 55

Thus, A

= √55

We are given to find sec, cot, and cosec, where is the angle shown in the figure, cos

= ?

= ?

= U 00 X c.8 A 3

The value of cos θ is given by the ratio of adjacent and hypotenuse sides of the right triangle.cosθ

= Adjacent side/Hypotenuse

= A/Cosθ

= √55/8

The value of secθ is the reciprocal of cosθ.secθ

= 1/cosθ

= 1/√55/8

= 8/√55

The value of cotθ is given by the ratio of adjacent and opposite sides of the right triangle.cotθ

= Adjacent/Opposite

= 3/√55.

The value of cosecθ is the reciprocal of sinθ.cosecθ

= 1/sinθcosecθ

= 1/3√55.

The required values aresecθ

= 8/√55,cotθ

= 3/√55,cosecθ

= 1/3√55.

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The polar curve equation of r = 72 sin θ represents a with an inner loop touching the pole at θ = π/2 and an outer loop having the pole at θ = 3π/2.

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The value of k is 2.

To determine the value of k in the given differential equation dy/dx = ky - 2y^6, we can examine the slope field associated with the equation. A slope field represents the behavior of the solutions to a differential equation by indicating the slope of the solution curve at each point.

By observing the slope field, we can identify the value of k that best matches the field's pattern. In this case, the slope field suggests that the slope at each point is determined by the difference between ky and 2y^6.

By comparing the equation with the slope field, we can see that the term ky - 2y^6 in the differential equation corresponds to the slope depicted in the field. Since the slope is determined by ky - 2y^6, we can conclude that k must equal 2.

Therefore, the value of k in the given differential equation is 2.

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The probability that 1 tram arrives can be represented by the function 0.25t * exp(-0.25t).

The probability mass function (PMF) for the number of trams X arriving at the St. Peter's Square tram stop every t minutes is given as:

p(x) = (0.25t)^x * exp(-0.25t) / x!

To find the probability that 1 tram arrives, we substitute x = 1 into the PMF:

p(1) = (0.25t)^1 * exp(-0.25t) / 1!

= 0.25t * exp(-0.25t)

The probability that 1 tram arrives can be represented by the function 0.25t * exp(-0.25t).

Please note that this probability depends on the value of t, which represents the time interval. Without a specific value of t, we cannot provide a numeric result for the probability. The function 0.25t * exp(-0.25t) represents the probability as a function of t, indicating how the probability of one tram arriving changes with different time intervals.

To calculate the specific probability, you need to substitute a particular value for t into the function 0.25t * exp(-0.25t) and evaluate the expression. This will give you the probability of one tram arriving at the St. Peter's Square tram stop within that specific time interval.

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The P-value for the given test is 0.0885.

Given, the test statistic for this test turned out to have the value z = 1.35.

Now, we need to compute the P-value.

So, we can find the P-value as

P-value = P (Z > z)

where P is the probability of the standard normal distribution.

Using the standard normal distribution table, we can find that P(Z > 1.35) = 0.0885

Thus, the P-value for the given test is 0.0885.

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The area of the shaded region is 0.02 (rounded to 0.0001).

The shaded region for a standard normal distribution curve has an area of 0.96.

To find the area of this region, we use the TI-84 Plus calculator and follow this steps:1. Press the "2nd" button and then the "Vars" button to bring up the "DISTR" menu.

2. Scroll down and select "2:normalcdf(".

This opens the normal cumulative distribution function.

3. Type in -10 and 2.326 to get the area to the left of 2.326 (since the normal distribution is symmetric).

4. Subtract this area from 1 to get the area to the right of 2.326.5.

Multiply this area by 2 to get the total shaded area.6. Round the answer to at least 0.0001.

Part 1 of 4 The area of the shaded region is 0.02 (rounded to 0.0001).

Part 2 of 4 To find the area to the left of 2.326, we enter -10 as the lower limit and 2.326 as the upper limit, like this: normalcy (-10,2.326)Part 3 of 4

This gives us an answer of 0.9897628097 (rounded to 10 decimal places).

Part 4 of 4 To find the area to the right of 2.326, we subtract the area to the left of 2.326 from 1, like this:1 - 0.9897628097 = 0.0102371903 (rounded to 10 decimal places).

Now we multiply this area by 2 to get the total shaded area:

0.0102371903 x 2 = 0.020474381 (rounded to 9 decimal places).

The area of the shaded region is 0.02 (rounded to 0.0001).

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The value of the derivative dy/dx for the curve [tex]x = 3te^{(3t)}, y = e^{(-9t)}[/tex] at the point (0,1) is -3.

To find the value of dy/dx for the curve [tex]x = 3te^{(3t)}, y = e^{(-9t)}[/tex] at the point (0,1), we need to differentiate y with respect to x using the chain rule.

Let's start by finding dx/dt and dy/dt:

[tex]dx/dt = d/dt (3te^(3t))\\ = 3e^(3t) + 3t(3e^(3t))\\ = 3e^(3t) + 9te^(3t)\\dy/dt = d/dt (e^(-9t))\\ = -9e^(-9t)\\[/tex]

Now, we can calculate dy/dx:

dy/dx = (dy/dt) / (dx/dt)

At the point (0,1), t = 0. Substituting the values:

[tex]dx/dt = 3e^(3 * 0) + 9 * 0 * e^(3 * 0)\\ = 3[/tex]

[tex]dy/dt = -9e^(-9 * 0)\\ = -9\\dy/dx = (-9) / 3\\ = -3\\[/tex]

Therefore, the value of dy/dx for the curve[tex]x = 3te^(3t), y = e^(-9t)[/tex] at the point (0,1) is -3.

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The value of dy/dx for the curve x = 3te^(3t), y = e^(-9t) at the point (0,1) is -9.

To find the value of dy/dx at the point (0,1), we need to differentiate the given parametric equations with respect to t and evaluate it at t = 0. Let's begin.

1. Differentiating x = 3te^(3t) with respect to t:

  Using the product rule, we get:

[tex]dx/dt = 3e\^ \ (3t) + 3t(3e\^ \ (3t))\\= 3e\^ \ (3t) + 9te\^ \ (3t)[/tex]

2. Differentiating y = e^(-9t) with respect to t:

  Applying the chain rule, we get:

[tex]dy/dt = -9e\^\ (-9t)[/tex]

3. Now, we need to find dy/dx by dividing dy/dt by dx/dt:

[tex]dy/dx = (dy/dt) / (dx/dt)\\= (-9e\^ \ (-9t)) / (3e\^ \ (3t) + 9te\^ \ (3t))[/tex]

To evaluate dy/dx at the point (0,1), substitute t = 0 into the expression:

[tex]dy/dx = (-9e\^ \ (-9(0))) / (3e\^ \ (3(0)) + 9(0)e\^ \ (3(0)))\\= (9) / (3)\\= -3[/tex]

Therefore, the value of dy/dx for the given curve at the point (0,1) is -3.

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The 95% confidence level upper bound on the turnout is 0.503.

To calculate the 95% confidence level upper bound on the turnout when 48.4% of voters voted for party A in an exit poll of 10,000 voters, we use the following formula:

Sample proportion = p = 48.4% = 0.484,

Sample size = n = 10,000

Margin of error at 95% confidence level = z*√(p*q/n),

where z* is the z-score at 95% confidence level and q = 1 - p.

Substituting the given values, we get:

Margin of error = 1.96*√ (0.484*0.516/10,000) = 0.019.

Therefore, the 95% confidence level upper bound on the turnout is:

Upper bound = Sample proportion + Margin of error =

0.484 + 0.019= 0.503.

The 95% confidence level upper bound on the turnout is 0.503.

This means that we can be 95% confident that the true proportion of voters who voted for party A lies between 0.484 and 0.503.

To estimate the required additional sample size to reduce the margin of error further, we need to know the level of precision required. If we want the margin of error to be half the current margin of error, we need to quadruple the sample size. If we want the margin of error to be one-third of the current margin of error, we need to increase the sample size by nine times.

Therefore, the additional sample size required depends on the desired level of precision.

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The 95% confidence interval for the proportion of cans in the shipment that meet the specification is approximately (0.753, 0.905).

We have,

To find the 95% confidence interval for the proportion of cans in the shipment that meet the specification, we can use the formula for a confidence interval for proportions.

The formula is:

Confidence Interval = Sample Proportion ± (Critical Value) x Standard Error

First, calculate the sample proportion:

Sample Proportion = Number of cans that meet specification / Sample Size

In this case, the number of cans that meet the specification is 58, and the sample size is 70:

Sample Proportion = 58 / 70 ≈ 0.829

Next, calculate the standard error:

Standard Error = sqrt((Sample Proportion x (1 - Sample Proportion)) / Sample Size)

Substituting the values:

Standard Error = √((0.829 x (1 - 0.829)) / 70) ≈ 0.039

Now, we need to find the critical value associated with a 95% confidence level.

For a two-tailed test, the critical value corresponds to an alpha level of 0.05 divided by 2, which gives us an alpha level of 0.025.

We can consult the standard normal distribution (Z-table) or use a calculator to find the critical value.

The critical value for a 95% confidence level is approximately 1.96.

Finally, we can calculate the confidence interval:

Confidence Interval = 0.829 ± (1.96) x 0.039

Calculating the expression within parentheses:

Confidence Interval = 0.829 ± 0.076

Therefore,

The 95% confidence interval for the proportion of cans in the shipment that meet the specification is approximately (0.753, 0.905).

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The probability of selecting a 5 given that a blue disk is selected is 2/7.What we need to find is the conditional probability of selecting a 5 given that a blue disk is selected.

This is represented as P(5 | B).We can use the formula for conditional probability, which is:P(A | B) = P(A and B) / P(B)In our case, A is the event of selecting a 5 and B is the event of selecting a blue disk.P(A and B) is the probability of selecting a 5 and a blue disk. From the diagram, we see that there are two disks that satisfy this condition: the blue disk with the number 5 and the blue disk with the number 2.

Therefore:P(A and B) = 2/10P(B) is the probability of selecting a blue disk. From the diagram, we see that there are four blue disks out of a total of ten disks. Therefore:P(B) = 4/10Now we can substitute these values into the formula:P(5 | B) = P(5 and B) / P(B)P(5 | B) = (2/10) / (4/10)P(5 | B) = 2/4P(5 | B) = 1/2Therefore, the probability of selecting a 5 given that a blue disk is selected is 1/2 or 2/4.

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The phrase "4 divided by the sum of 4 and a number" can be translated into an algebraic expression as 4 / (4 + x). In this expression,

'x' represents the unknown number. The numerator, 4, indicates that we have 4 units. The denominator, (4 + x), represents the sum of 4 and the unknown number 'x'. Dividing 4 by the sum of 4 and 'x' gives us the ratio of 4 to the total value obtained by adding 4 and 'x'.

This algebraic expression allows us to calculate the result of dividing 4 by the sum of 4 and any given number 'x'.

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The exact value of the expression using reference triangles is: `-0.53104 × 0.88386 × 1.13427 = -0.5151` (rounded to four decimal places). Hence, the solution to the given problem is `-0.5151`.

Given that the expression is `(tan-1152-800-12) COS sec

We need to find the exact value of the expression using reference triangles.

To find the exact value of the expression using reference triangles, we need to draw a reference triangle.

Here is the reference triangle:

We can find the length of adjacent side OX by using the Pythagorean theorem:```
OQ^2 = OP^2 + PQ^2
PQ = 800 meters (Given)
OP = 12 meters (Given)
OQ^2 = 800^2 + 12^2
OQ^2 = 640144
OQ = sqrt(640144)
OQ = 800.09 meters (rounded to two decimal places)
Now we can use this reference triangle to find the exact value of the expression.

Tan(-1152) = -tan(180°-1152°)=-tan(28°)=-0.53104 (rounded to five decimal places)Cos(28°)=0.88386 (rounded to five decimal places)Sec(28°)=1.13427 (rounded to five decimal places)

Therefore, the exact value of the expression using reference triangles is: `-0.53104 × 0.88386 × 1.13427 = -0.5151` (rounded to four decimal places). Hence, the solution to the given problem is `-0.5151`.

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a) f(x₁, x₂, ..., xₙ) = 3x₁² * 3x₂² * ... * 3xₙ² is the joint pdf of X1, X2, ..., Xn.

b) 0.125 is the probability that all of the observations are less than 0.5.

c) (0.125)ⁿ is the probability that all of the observations are less than 0.5.

(a) The joint pdf of X1, X2, ..., Xn is given by the product of the individual pdfs since the random variables are independent. Therefore, the joint pdf can be expressed as:

f(x₁, x₂, ..., xₙ) = f(x₁) * f(x₂) * ... * f(xₙ)

Since the pdf f(x) = 3x^2 for 0 < x < 1 and zero otherwise, the joint pdf becomes:

f(x₁, x₂, ..., xₙ) = 3x₁² * 3x₂² * ... * 3xₙ²

(b) To find the probability that the first observation is less than 0.5, P(X₁ < 0.5), we integrate the joint pdf over the given range:

P(X₁ < 0.5) = ∫[0.5]₀ 3x₁² dx₁

Integrating, we get:

P(X₁ < 0.5) = [x₁³]₀.₅ = (0.5)³ = 0.125

Therefore, the probability that the first observation is less than 0.5 is 0.125.

(c) To find the probability that all of the observations are less than 0.5, we take the product of the probabilities for each observation:

P(X₁ < 0.5, X₂ < 0.5, ..., Xₙ < 0.5) = P(X₁ < 0.5) * P(X₂ < 0.5) * ... * P(Xₙ < 0.5)

Since the random variables are independent, the joint probability is the product of the individual probabilities:

P(X₁ < 0.5, X₂ < 0.5, ..., Xₙ < 0.5) = (0.125)ⁿ

Therefore, the probability that all of the observations are less than 0.5 is (0.125)ⁿ.

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a) 0.0062 is the probability that the student completes the exam in less than 45 minutes.

b) 77.4 minutes should be given to complete the exam so 80% of the students will complete the exam in the time given.

a) The probability that a student completes the exam in less than 45 minutes can be calculated using the standard normal distribution. By converting the given values to z-scores, we can use a standard normal distribution table or a calculator to find the probability.

To convert the given time of 45 minutes to a z-score, we use the formula: z = (x - μ) / σ, where x is the given time, μ is the mean, and σ is the standard deviation. Substituting the values, we get z = (45 - 70) / 10 = -2.5.

Using the standard normal distribution table or a calculator, we can find that the probability corresponding to a z-score of -2.5 is approximately 0.0062.

Therefore, the probability that a student completes the exam in less than 45 minutes is approximately 0.0062, or 0.62%.

b) To determine the time needed for 80% of the students to complete the exam, we need to find the corresponding z-score for the cumulative probability of 0.8.

Using the standard normal distribution table or a calculator, we find that the z-score corresponding to a cumulative probability of 0.8 is approximately 0.84.

Using the formula for z-score, we can solve for the time x: z = (x - μ) / σ. Rearranging the formula, we get x = μ + (z * σ). Substituting the values, we get x = 70 + (0.84 * 10) = 77.4.

Therefore, approximately 77.4 minutes should be given to complete the exam so that 80% of the students will complete it within the given time.

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The class boundaries for the first class interval are:Lower limit = 32Upper limit = 34Class width = 3Boundaries = 32 - 1.5 = 30.5 and 34 + 1.5 = 35.5. The boundaries for the remaining class intervals can be determined in a similar manner. Therefore, the class boundaries are given below:Temperature (°F)FrequencyClass boundaries32-34130.5-35.535-3735-38.540-4134.5-44.544-4638.5-47.547-4944.5-52.550-5264.5-79.5

The frequency distribution table is given below:Temperature (°F)Frequency32-34135-3738-4041-4344-4647-4950-521The frequency distribution gives a range of values for the temperature in Fahrenheit. In order to answer the questions (a), (b) and (c), the class width, class midpoints, and class boundaries need to be determined.(a) Class WidthThe class width can be determined by subtracting the lower limit of the first class interval from the lower limit of the second class interval. The lower limit of the first class interval is 32, and the lower limit of the second class interval is 35.32 - 35 = -3Therefore, the class width is 3. The answer is 3.(b) Class MidpointsThe class midpoint can be determined by finding the average of the upper and lower limits of the class interval. The class intervals are given in the frequency distribution table. The midpoint of the first class interval is:Lower limit = 32Upper limit = 34Midpoint = (32 + 34) / 2 = 33The midpoint of the second class interval is:Lower limit = 35Upper limit = 37Midpoint = (35 + 37) / 2 = 36. The midpoint of the remaining class intervals can be determined in a similar manner. Therefore, the class midpoints are given below:Temperature (°F)FrequencyMidpoint32-34133.535-37361.537-40393.541-4242.544-4645.547-4951.550-5276(c) Class BoundariesThe class boundaries can be determined by adding and subtracting half of the class width to the lower and upper limits of each class interval. The class width is 3, as determined above. Therefore, the class boundaries for the first class interval are:Lower limit = 32Upper limit = 34Class width = 3Boundaries = 32 - 1.5 = 30.5 and 34 + 1.5 = 35.5. The boundaries for the remaining class intervals can be determined in a similar manner. Therefore, the class boundaries are given below:Temperature (°F)FrequencyClass boundaries32-34130.5-35.535-3735-38.540-4134.5-44.544-4638.5-47.547-4944.5-52.550-5264.5-79.5.

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A randomization test with 10,000 randomizations found that the absolute difference between group means was greater than or equal to 2 mm in 490 of the randomizations. We can conclude that there was a marginally significant difference between groups (p = 0.049).

Randomization tests are used to examine the null hypothesis that two populations have similar characteristics. The hypothesis testing approach used in statistics is a formal method of decision-making based on data. In hypothesis testing, a null hypothesis and an alternative hypothesis are used to determine if the results of the data support the null hypothesis or the alternative hypothesis. A p-value is calculated and compared to a significance level (usually 0.05) to determine whether the null hypothesis should be rejected or not. In this scenario, the difference in mean size between shells taken from sheltered and exposed reefs was found to be 2 mm. A randomization test with 10,000 randomizations found that the absolute difference between group means was greater than or equal to 2 mm in 490 of the randomizations. Since the number of randomizations in which the absolute difference between group means was greater than or equal to 2 mm was less than the significance level (0.05), we can conclude that there was a marginally significant difference between groups (p = 0.049).

We can conclude that there was a marginally significant difference between groups (p = 0.049).

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We can reject the null hypothesis and conclude that there is a marginally significant difference between groups (p = 0.049)

To solve this problem, we need to perform a hypothesis test where:

Null Hypothesis, H0: There is no difference between the two groups.

Alternate Hypothesis, H1: There is a difference between the two groups.

Here, the mean difference between the two groups is given to be 2 mm. Also, we are given that 490 out of 10000 randomizations have an absolute difference between group means of 2 mm or more.

The p-value can be calculated by the following formula:

p-value = (number of randomizations with an absolute difference between group means of 2 mm or more) / (total number of randomizations)

Substituting the given values in the above formula, we get:

p-value = 490 / 10000p-value = 0.049

Therefore, the p-value is 0.049 which is less than 0.05. Hence, we can reject the null hypothesis and conclude that there is a marginally significant difference between groups (p = 0.049).

The correct option is (e) There was a marginally significant difference between groups (p = 0.049).

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The number of Camaros sold by season is a discrete variable.

For this problem, the variable is the number of cars sold, which cannot assume decimal values, as for each, there cannot be half a car sold.

As the number of cars sold can assume only whole numbers, we have that it is a discrete variable.

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The given statement is false as an assumption of non-parametric tests is that the distribution does not need to be normal.

Question 2The given statement is true as chi-square tests can be used when the data is measured on a nominal scale. Question 3The observed frequencies for a chi-square test can contain fractions or decimal values. Question 4The term expected frequencies refers to the frequencies that are hypothesized for the population being examined. The expected frequencies are computed from the null hypothesis found in the sample data.The chi-square test is a non-parametric test used to determine the significance of how two or more frequencies are different in a particular population. The non-parametric test means that the distribution is not required to be normal. Instead, this test relies on the sample data and frequency counts.The chi-square test can be used for nominal scale data or categorical data. The observed frequencies for a chi-square test can contain fractions or decimal values. However, the expected frequencies are computed from the null hypothesis found in the sample data. The expected frequencies are the frequencies that are hypothesized for the population being examined. Therefore, option D correctly describes the expected frequencies.

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The headings that correctly complete the chart are x: snakes, y: turtles.

To determine the correct headings that complete the chart, we need to consider the relationship between the variables and their respective values. The chart is likely displaying a relationship between two variables, x and y. We need to identify what those variables represent based on the given options.

Option a. x: turtles, y: crocodilians:

This option suggests that turtles are represented by the x-values and crocodilians are represented by the y-values. However, without further context, it is unclear how these variables relate to each other or what the chart is measuring.

Option b. x: crocodilians, y: turtles:

This option suggests that crocodilians are represented by the x-values and turtles are represented by the y-values. Again, without additional information, it is uncertain how these variables are related or what the chart is representing.

Option c. x: snakes, y: turtles:

This option suggests that snakes are represented by the x-values and turtles are represented by the y-values. This combination of variables seems more plausible, as it implies a potential relationship or comparison between snakes and turtles.

Option d. x: crocodilians, y: snakes:

This option suggests that crocodilians are represented by the x-values and snakes are represented by the y-values. While this combination is also possible, it does not match the given options in the chart.

Considering the options and the given chart, the most reasonable choice is: c. x: snakes, y: turtles.

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In the given problem, the descriptive statistics for home loan repayments in mid-2020 are as follows: Mean = 1301.91Standard error = 22.77Standard deviation = 161n = 50Now, let's look at some of the basic terms that are used in statistics, which are Mean, Median, Mode, and Range.

Mean is the average value of the dataset. Median is the middle value of the dataset. Mode is the value that occurs most frequently in the dataset. Range is the difference between the maximum and minimum values of the dataset. Hence, answering the given questions:What is the Mean value of home loan repayments?The mean value of home loan repayments is 1301.91. It is the average value of the given dataset.What is the Standard Error of home loan repayments?The standard error of home loan repayments is 22.77.

It tells us how much the sample mean is likely to differ from the true population mean.What is the Standard Deviation of home loan repayments?The standard deviation of home loan repayments is 161. It tells us how much the data values deviate from the mean value. A higher standard deviation indicates that the data values are more spread out.How many observations (n) are included in the dataset?The number of observations (n) included in the dataset is 50. It tells us the sample size of the given dataset.

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The required probability of obtaining a z value between -2.4 to -2.0 is 0.0146.

Given, for a standard normal distribution, the probability of obtaining a z value between -2.4 to -2.0 is.

Now, we have to find the probability of obtaining a z value between -2.4 to -2.0.

To find this, we use the standard normal table which gives the area to the left of the z-score.

So, the required probability can be calculated as shown below:

Let z1 = -2.4 and z2 = -2.0

Then, P(-2.4 < z < -2.0) = P(z < -2.0) - P(z < -2.4)

Now, from the standard normal table, we haveP(z < -2.0) = 0.0228 and P(z < -2.4) = 0.0082

Substituting these values, we get

P(-2.4 < z < -2.0) = 0.0228 - 0.0082= 0.0146

Therefore, the required probability of obtaining a z value between -2.4 to -2.0 is 0.0146.

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customers feel more confident in the products and services they buy, which can lead to more business opportunities.

Dollar store discovers and returns $150 of defective merchandise purchased on November 1, and paid for on November 5, for a cash refund. When it comes to business, customers' satisfaction is important. If they are not happy with your product or service, they can report a problem and demand a refund. It seems like the Dollar store has followed the same customer satisfaction policy. According to the given scenario, the defective merchandise worth $150 was purchased on November 1st and was paid on November 5th. After purchasing, Dollar store discovered that the products were not up to the mark. They immediately decided to refund the customer's payment of $150 in cash. This decision was made due to two reasons: to satisfy the customer and to maintain the company's reputation. These kinds of incidents help to improve customer satisfaction and build customer loyalty. In addition, customers feel more confident in the products and services they buy, which can lead to more business opportunities.

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The length of segment PL in the triangle is 7.

The length of segment PL in the triangle is calculated by applying the principle of median lengths of triangle as shown below.

From the diagram, we can see that;

length OL and JM are not in the same proportion

Using the principle of proportion, or similar triangles rules, we can set up the following equation and calculate the value of length PL as follows;

Length OP is congruent to length PM

length PM is given as 2, then Length OP = 2

Since the total length of OL is given as 9, the value of missing length PL is calculated as;

PL = OL - OP

PL = 9 - 2

PL = 7

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