Fatima purchased a new mattress when it was on sale. The sale price was 27% less than the regular price. If the sale price was $409, what was the original price? (Round your answer to the nearest dollar).

Answer:

73,188

Step-by-step explanation:

fees plus costs minus expenses

Answer:

The point estimate that should be used in constructing the confidence interval is 3.5.

The 95% confidence interval for the true mean difference between the mean height of the American students and the mean height of the non-American students, in inches, is (2.25, 4.75).

Step-by-step explanation:

Before building the confidence interval, we need to understand the central limit theorem and subtraction of normal variables.

Central Limit Theorem

The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

Subtraction between normal variables:

When two normal variables are subtracted, the mean is the difference of the means, while the standard deviation is the square root of the sum of the variances.

American students:

Sample of 12, mean height of 68.4 inches with a standard deviation of 1.64 inches. This means that:

[tex]\mu_A = 68.4[/tex]

[tex]s_A = \frac{1.64}{\sqrt{12}} = 0.4743[/tex]

Non-American students:

Sample of 17, mean height of 64.9 inches with a standard deviation of 1.75 inches. This means that:

[tex]\mu_N = 64.9[/tex]

[tex]s_N = \frac{1.75}{\sqrt{17}} = 0.4244[/tex]

Distribution of the difference:

[tex]\mu = \mu_A - \mu_N = 68.4 - 64.9 = 3.5[/tex]

[tex]s = \sqrt{s_A^2+s_N^2} = \sqrt{0.4743^2 + 0.4244^2} = 0.6365[/tex]

The point estimate that should be used in constructing the confidence interval is 3.5.

Confidence interval:

[tex]\mu \pm zs[/tex]

In which

z is the z-score that has a p-value of [tex]1 - \frac{\alpha}{2}[/tex].

95% confidence level

So [tex]\alpha = 0.05[/tex], z is the value of Z that has a p-value of [tex]1 - \frac{0.05}{2} = 0.975[/tex], so [tex]Z = 1.96[/tex].  

The lower bound of the interval is:

[tex]\mu - zs = 3.5 - 1.96*0.6365 = 2.25[/tex]

The upper bound of the interval is:

[tex]\mu + zs = 3.5 + 1.96*0.6365 = 4.75[/tex]

The 95% confidence interval for the true mean difference between the mean height of the American students and the mean height of the non-American students, in inches, is (2.25, 4.75).

Answer:

The equation of the point (4, 12) is y=4x+12

Answer:

Red ball=3/10

White ball=1/5

Step-by-step explanation:

Red balls=6. And all the balls are equal to 20. So probability of red ball=6/20=3/10.

White balls=4. So probability of white ball=4/20=1/5.

NB: Since the first ball was replaced, there's no need to deduct a ball from the original 20 balls.

Answer:

a) 0.1927 = 19.27% probability that none of the selected adults say that they were too young to get tattoos.

b) 0.3651 = 36.51% probability that exactly one of the selected adults says that he or she was too young to get tattoos.

c) 0.5578 = 55.78% probability that the number of selected adults saying they were too young is 0 or 1.

Step-by-step explanation:

For each person, there are only two possible outcomes. Either they say they were too young to get tattoos, or they do not say this. The probability of a person saying this is independent of any other person, which means that the binomial probability distribution is used to solve this question.

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]

In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.

[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]

And p is the probability of X happening.

24​% say that they were too young when they got their tattoos.

This means that [tex]p = 0.24[/tex]

Six adults

This means that [tex]n = 6[/tex]

a. Find the probability that none of the selected adults say that they were too young to get tattoos.

This is P(X = 0). So

[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]

[tex]P(X = 0) = C_{6,0}.(0.24)^{0}.(0.76)^{6} = 0.1927[/tex]

0.1927 = 19.27% probability that none of the selected adults say that they were too young to get tattoos.

b. Find the probability that exactly one of the selected adults says that he or she was too young to get tattoos.

This is P(X = 1). So

[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]

[tex]P(X = 1) = C_{6,1}.(0.24)^{1}.(0.76)^{5} = 0.3651[/tex]

0.3651 = 36.51% probability that exactly one of the selected adults says that he or she was too young to get tattoos.

c. Find the probability that the number of selected adults saying they were too young is 0 or 1.

This is:

[tex]p = P(X = 0) + P(X = 1) = 0.1927 + 0.3651 = 0.5578[/tex]

0.5578 = 55.78% probability that the number of selected adults saying they were too young is 0 or 1.

Answer:

Step-by-step explanation:

x=120°

Answer:

The score of a person who did better than 85% of all the test-takers was of 624.44.

Step-by-step explanation:

Normal Probability Distribution

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

One year, the average score on the Math SAT was 500 and the standard deviation was 120.

This means that [tex]\mu = 500, \sigma = 120[/tex]

What was the score of a person who did better than 85% of all the test-takers?

The 85th percentile, which is X when Z has a p-value of 0.85, so X when Z = 1.037.

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]1.037 = \frac{X - 500}{120}[/tex]

[tex]X - 500 = 1.037*120[/tex]

[tex]X = 624.44[/tex]

The score of a person who did better than 85% of all the test-takers was of 624.44.

9514 1404 393

Answer:

  c. y = (x +2)² -5

Step-by-step explanation:

If you replace the squared term with zero, you are choosing the minimum of the remaining values. (A squared term cannot have a negative value.)

  a) 3

  b) 4

  c) -5 . . . . the graph with the least possible y-value

  d) 0

Answer:

1=2p+3

2=

Step-by-step explanation:

Answer:

Start with the formula for Z:

Z = (x-µ)/(σ/√n)

We want the sample mean to be within one-half year of the population mean, so we set x-µ=0.5. We are looking for a 99% confidence interval, so we set Z=2.7578. We are told to use σ=18.1. Plugging those values into the formula, we get:

2.5758 = 0.5(18.1/√n)

We can rearrange to solve for n:

((2.5758-18.1)/0.5)2 = n

Plugging that into our calculator, we get n = 964.003. Since we can't have a fraction of a person in our sample, it would be safest to round up to n=965. (But since .003 is so small, I'd also accept 964 as an answer.)Step-by-step explanation:

The required sample size for the given population distribution is; n = 8696 female ages

We are given;

Standard deviation; σ = 18.1

Confidence level; CL = 99%

Now, formula to find the margin of error is;

E = z(σ/√n)

Where;

E is margin of error

z is critical value at confidence level

σ is standard deviation

n is required sample size

Now we are told that the sample mean is within one-half year of the population mean.

Thus;

E = 0.5

z value at 99% Confidence level is;

z = 2.576

Thus, Making n the subject of the formula is;

n = (zσ/E)²

n = (2.576 × 18.1/0.5)²

n = 8695.78

Approximating to a whole number gives;

n = 8696 female ages

Read more about margin of error at; https://brainly.com/question/6650225

the answer would be -1,224 because the parentheses is your multiplication and the it is a negative

9514 1404 393

Answer:

Step-by-step explanation:

Let x represent the quantity of 15% alcohol required. Then (5-x) is the amount of 10% alcohol needed. The amount of alcohol in the mix is ...

  0.15x +0.10(5-x) = 0.13(5)

  0.05x +0.5 = 0.65 . . . . . . . simplify

  0.05x = 0.15 . . . . . . . . . subtract 0.5

  x = 3 . . . . . . . . . . . . . divide by 0.05

3 gallons of 15% alcohol and 2 gallons of 10% alcohol should be mixed.

Answer:

Decreased by 20%

Step-by-step explanation:

0.5 x ? = 0.4

? = 0.4/0.5

? = 0.8

1 - 0.8 = 0.2

0.2 = 20%

To check, 20% of 0.5 is 0.1. 0.5 - 0.1 is 0.4. So the answer is correct.

Answer:

2520

Step-by-step explanation:

210×12=2520

2520three

Answer:

The answer would be D

Step-by-step explanation:

This is a piecewise function, meaning that it is split into two parts. The right side is an exponential and that part is greater than one, the left side is a line less than or equal to one. The only equation that matches the criteria for that is D.

Answer:

b 34 the higest is 40 an the lowest 6 the diferens is 34

Step-by-step explanation:

Mark me brainlest pliz

Answer:

i would but this not my question this is theres he right A.

Step-by-step explanation:

Answer:

Using z table

                         = 0.0013

The probability = 0.0013

Step-by-step explanation:

Given that,

mean = μ = 45

standard deviation = σ   = 9

n=81

μT = μ =45

[tex]\sigma T = \sigma / \sqrt n = 9 / \sqrt81 =1[/tex]

[tex]P(T <42 )\\= P[(T - \mu T ) / \sigma T < (42-45) /1 ]\\\\= P(z <-3 )[/tex]

Using z table

= 0.0013

probability= 0.0013

Answer:

5886$ is the ans

Step-by-step explanation:

Paid amount= 6000-600

Total Amount or Interest applicable amount = 5400$

Then

Interest Rate= 9%

by using formula

=. Total amount + Interest rate × Total

=. 5400+0.09×5400

=. 5886$

Answer:

10!

Step-by-step explanation:

Septillion-10 letters

1-s-10 places to be in

2-e-9

3-p-8

4-t-7

5-i-6

6-l-5

7-l-4

8-i-3

9-o-2

10-n-1

So, then

10×9×8×7×6×5×4×3×2×1=10!

or 3628800

The arrangement of the number will be equal to 3628800.

A permutation is an orderly arrangement of things or numbers. Combinations are a way to choose items or numbers from a collection or group of items without worrying about the items' chronological order.

A combination in mathematics is a choice made from a group of separate elements where the order of the selection is irrelevant.

The given word is SEPTILLION. The word has 10 characters. The different ways of the arrangement will be calculated as,

Arrangement = 10!

Arrangement = 10×9×8×7×6×5×4×3×2×1

Arrangement = 3628800

Therefore, the arrangement of the number will be equal to 3628800.

To know more about permutation and combination follow

https://brainly.com/question/4658834

#SPJ2

Answer:

a.5

b.3a+3

Step-by-step explanation:

in a,u need to replace 2 with x,so it will be 4-2+3

in b,replace 3a with x and so it will be6a-3a+3

In triangle it is given that,

→ Height (h) = 38 cm

→ Base (b) = 44 cm

The formula we use,

→ Area of triangle = ½ × b × h

Now we have to,

find the area of the triangle,

→ ½ × b × h

→ ½ × 44 × 38

→ (44 × 38)/2

→ 1672/2 = 836 cm²

So, 836 cm² is area of triangle.

Answer:

The constant is StartFraction 5 over 6 EndFraction

Step-by-step explanation:

StartFraction 5 over 6 EndFraction + one-fourth x minus y

5/6 + 1/4x - y

A. The constant is StartFraction 5 over 6 EndFraction.

True

B. The only coefficient is One-fourth.

False

There are two coefficients: the coefficient of x which is 1/4 and the coefficient of y which is 1

C. The only variable is y

False

There are 2 variables: variable x and variable y

D. The terms StartFraction 5 over 6 EndFraction and One-fourth x are like terms.

False

5/6 and 1/4x are not like terms

The only true statement is: The constant is StartFraction 5 over 6 EndFraction

Answer:

It's A if you don't want to read. A). The constant is 5/6

Step-by-step explanation:

Answer:

S/100r

Step-by-step explanation:

S% of 1/r = (1/r x S) : 100

(1/r x S) : 100

S/r : 100

S/100r

Answer:

(x, y, z) = (-8,4,-2)

Step-by-step explanation:

.......................................

Answer:

x^(d+18)

Step-by-step explanation:

using the law of indices

you must add the powers

Answer:

[tex] {x}^{d + 18} [/tex]

Step-by-step explanation:

9514 1404 393

Answer:

  (i) k = 1

  (ii) 4/7

  (iii) arctan(4/7) ≈ 29.7°

Step-by-step explanation:

(i) A graph of the given points is helpful. It shows us the slope of AB is ...

  mAB = rise/run = 2/1 = 2

so the slope of BC must be the opposite reciprocal, -1/2.

Point C is 6-2 = 4 units to the right of point B, so will be (-1/2)(4) = -2 units from point B in the vertical direction. That is, ...

  k = 3 -2

  k = 1

__

(ii) The gradient of AC is found from the slope formula:

  m = (y2 -y1)/(x2 -x1)

  m = (1 -(-3))/(6 -(-1))

  mAC = 4/7

__

(iii) The angle that line AC makes with the +x axis is the arctangent of the slope:

  arctan(4/7) ≈ 29.7° . . . angle between AC and +x axis

9514 1404 393

Answer:

  $794.30

Step-by-step explanation:

The account balance for principal P invested at rate r compounded daily for t years is ...

  A = P(1 +r/365)^(365t)

We have P=$9538, r=0.08, t=1, and we want the value of P-A, the interest earned.

  P-A = P(1 +0.08/365)^365 -1) = $9538(1.08327757 -1) ≈ $794.30

The interest earned in one year is $794.30.

Answer

There are 170 ways the student can answer the test.

Explanation

If there are 20 multiple-choice questions with 5 choices each, the student has 100 choices. The first question has 5 choices to pick from. The second has 5 as well. So does the third. Hopefully now you realize that you have to multiply the number of choices by the number of questions.

The same thing goes with the true/false questions. There are 2 choices for each true/false question, and there are 35 of those. 35×2 is 70. There are 70 ways to answer on the true/false questions.

Now combine the number of choices on the first part and the second part; 100+70 is 170.

The base of the solid - call it B - is the set of points

B = {(x, y) : 0 ≤ x ≤ 1 and x ⁴ ≤ y ≤ 1}

Recall the area of a circle with radius r is πr ²; in terms of the diameter d = 2r, the area is π (d/2)² = π/4 d ². Then the area of a semicircle with the same diamater is half of this, π/8 d ².

Cross sections of the solid in question are semicircles arranged perpendicular to the x-axis, which means the diameters of each cross section corresponds to the vertical distance between y = x ⁴ and y = 1 for any given values of x between 0 and 1. So d = 1 - x ⁴, which makes the area of each cross section come out to π/8 (1 - x ⁴)².

Split up the solid into very thin cross sections with "base" area π/8 (1 - x ⁴)² and thickness ∆x. Take the sum of these half-cylinders' volumes, then let ∆x converge to 0. In short, we get the total volume by integrating,

[tex]\displaystyle \int_0^1\frac\pi8(1-x^4)^2\,\mathrm dx = \frac\pi8\int_0^1(1-2x^4+x^8)\,\mathrm dx = \boxed{\frac{4\pi}{45}}[/tex]

Answer:

6

Step-by-step explanation:

f(x) = 2(x - 5)

f(8) = 2(8 - 5)

f(8) = 16 - 10

f(8) = 6

The answer is 6, hope this helps.

[tex]\boxed{ \sf{Answer}} [/tex]

[tex]\sf \: f(x) = 2(x - 5) \\ \\\sf x = 8 \\ \\\sf f(8) = 2(8 - 5) \\\sf \: f(8) = 2(3) \\ \sf \: f(8) = 2 \times 3 \\\sf f(8) =\underline 6[/tex]

Option B - 06 is the correct answer.

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