Answer:
Bro what to do in this question I am not able to understand Hope you understand me
A random sample of 10 sales receipts for internet sales results in a mean sale amount of $66.30 with a standard deviation of $15.75. Using this data, find the 98% confidence interval for the true mean difference between the mean amount of mail-order purchases and the mean amount of internet purchases. Assume that the population variances are not equal and that the two populations are normally distributed. Step 1 of 3 : Find the point estimate that should be used in constructing the confidence interval.
Answer:
ur mum s house
Step-by-step explanation:
myueudifigkgkgogkvkcv
Evaluate the expression when a=-7 and y=3 3y-a
Answer:
3y-a
3.3-7
9-7
2
Step-by-step explanation:
first we have to do multiply by replacing the value of y and the subtract by using the value of a.
Hope this will be helpful for you
What type of object is pictured below?
O A. Point
O B. Ray
C. Segment
D. Line
Answer:
It is a ray because there are two points with a line passing through them which is extenging on one side but not on the other.
See above. okokokoookkokokokokkkkokokkokokkok
Answer:
B
Step-by-step explanation:
B is the correct answer
Is this true or false ??
=============================================================
Explanation:
We'll use these two properties of integrals [tex]\displaystyle \text{If f(x) is an even function, then } \int_{-a}^{a}f(x)dx = 2\int_{0}^{a}f(x)dx[/tex]
[tex]\displaystyle \text{If f(x) is an odd function, then } \int_{-a}^{a}f(x)dx = 0[/tex]
These properties are valid simply because of the function's symmetry. For even functions, we have vertical axis symmetry about x = 0; while odd functions have symmetry about the origin.
------------------------
Here's how the steps could look
[tex]\displaystyle \int_{-7}^{7}(ax^8+bx+c)dx=\int_{-7}^{7}((ax^8+c)+bx)dx\\\\\\\displaystyle \int_{-7}^{7}(ax^8+bx+c)dx=\int_{-7}^{7}(ax^8+c)dx+\int_{-7}^{7}(bx)dx\\\\\\\displaystyle \int_{-7}^{7}(ax^8+bx+c)dx=\left(2\int_{0}^{7}(ax^8+c)dx\right)+(0)\\\\\\\displaystyle \int_{-7}^{7}(ax^8+bx+c)dx=2\int_{0}^{7}(ax^8+c)dx\\\\\\[/tex]
Therefore, the given statement is true. The values of a,b,c don't matter. You could replace those '7's with any real number you want and still end up with a true statement.
We can see that ax^8+c is always even, while bx is always odd.
------------------------
Side note:
For the second step, I used the idea that [tex]\int(f(x)+g(x))dx=\int f(x)dx+\int g(x)dx\\\\[/tex]
which allows us to break up a sum into smaller integrals.
A study on the latest fad diet claimed that the amounts of weight lost by all people on this diet had a mean of 21.9 pounds and a standard deviation of 5.3 pounds.
Step 2 of 2 :
If a sampling distribution is created using samples of the amounts of weight lost by 78 people on this diet, what would be the standard deviation of the sampling distribution of sample means? Round to two decimal places, if necessary.
Answer:
The standard deviation of the sampling distribution of sample means would be of 0.7 pounds.
Step-by-step explanation:
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.
Mean of 21.9 pounds and a standard deviation of 5.3 pounds.
This means that [tex]\mu = 21.9, \sigma = 5.3[/tex]
If a sampling distribution is created using samples of the amounts of weight lost by 78 people on this diet, what would be the standard deviation of the sampling distribution of sample means?
This is s when n = 78, so:
[tex]s = \frac{5.3}{\sqrt{78}} = 0.6[/tex]
The standard deviation of the sampling distribution of sample means would be of 0.7 pounds.
A half-century ago, the mean height of women in a particular country in their 20s was inches. Assume that the heights of today's women in their 20s are approximately normally distributed with a standard deviation of inches. If the mean height today is the same as that of a half-century ago, what percentage of all samples of of today's women in their 20s have mean heights of at least inches?
Answer:
0.26684
Step-by-step explanation:
Given that :
Mean, μ = 62.5
Standard deviation, σ = 1.96
P(Z ≥ 63.72)
The Zscore = (x - μ) / σ
P(Z ≥ (x - μ) / σ)
P(Z ≥ (63.72 - 62.5) / 1. 96) = P(Z ≥ 0.6224)
P(Z ≥ 0.6224) = 1 - P(Z < 0.6224)
1 - P(Z < 0.6224) = 1 - 0.73316 = 0.26684
Suppose the daily customer volume at a call center has a normal distribution with mean 5,500 and standard deviation 1,000. What is the probability that the call center will get between 4,800 and 5,000 calls in a day
Answer:
0.0665 = 6.65% probability that the call center will get between 4,800 and 5,000 calls in a day.
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.
Mean 5,500 and standard deviation 1,000.
This means that [tex]\mu = 5500, \sigma = 1000[/tex]
What is the probability that the call center will get between 4,800 and 5,000 calls in a day?
This is the p-value of Z when X = 5000 subtracted by the p-value of Z when X = 4800. So
X = 5000
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{5000 - 5500}{1000}[/tex]
[tex]Z = -0.5[/tex]
[tex]Z = -0.5[/tex] has a p-value of 0.3085.
X = 4800
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{4800 - 5500}{1000}[/tex]
[tex]Z = -0.7[/tex]
[tex]Z = -0.7[/tex] has a p-value of 0.2420.
0.3085 - 0.2420 = 0.0665
0.0665 = 6.65% probability that the call center will get between 4,800 and 5,000 calls in a day.
Construct the confidence interval for the population standard deviation for the given values. Round your answers to one decimal place. n=21 , s=3.3, and c=0.9
Answer:
The correct answer is "[tex]2.633< \sigma < 4.480[/tex]".
Step-by-step explanation:
Given:
n = 21
s = 3.3
c = 0.9
now,
[tex]df = n-1[/tex]
[tex]=20[/tex]
⇒ [tex]x^2_{\frac{\alpha}{2}, n-1 }[/tex] = [tex]x^2_{\frac{0.9}{2}, 21-1 }[/tex]
= [tex]31.410[/tex]
⇒ [tex]x^2_{1-\frac{\alpha}{2}, n-1 }[/tex] = [tex]10.851[/tex]
hence,
The 90% Confidence interval will be:
= [tex]\sqrt{\frac{(n-1)s^2}{x^2_{\frac{\alpha}{2}, n-1 }} } < \sigma < \sqrt{\frac{(n-1)s^2}{x^2_{1-\frac{\alpha}{2}, n-1 }}[/tex]
= [tex]\sqrt{\frac{(21-1)3.3^2}{31.410} } < \sigma < \sqrt{\frac{(21.1)3.3^2}{10.851} }[/tex]
= [tex]\sqrt{\frac{20\times 3.3^2}{31.410} } < \sigma < \sqrt{\frac{20\times 3.3^2}{10.851} }[/tex]
= [tex]2.633< \sigma < 4.480[/tex]
Brendan has $65 worth of balloons and flowers delivered to his mother. He pays the bill plus an 8.5% sales tax and an 18% tip on the total cost including tax. He also pays a $10 delivery fee that is charged after the tax and tip. How much change does he receive if he pays with two $50 bills? Round to the nearest cent.
Answer:
its 6.78 i believe
Step-by-step explanation:
The delivery man checks his route for deliveries.
The map has a scale of 1:250,000.
The distance between the bakery and his last delivery is 35 cm
What is the actual distance?
km.
9514 1404 393
Answer:
87.5 km
Step-by-step explanation:
Actual distance is 250000×35 cm = 87.5×10^5 cm = 87.5 km
_____
There are 100 cm in 1 m, and 1000 m in 1 km, so 100,000 cm = 10^5 cm in 1 km
Which explains whether or not the graph represents a direct variation?
Answer:
The slope is 3 and equation of the line is y=3x. I think the answer is the 1st option
Step-by-step explanation:
Given:
y=3x
Direct variation equations have the form:
y=kx,
where
k is the constant of proportionality
so k=3
Help Please ASAP!!! Not sure how to solve this problem. Can someone help me please? Thank you for your help!
Answer:
This question is formatted incorrectly
Step-by-step explanation:
i need the answer no explanation
Answer:
the answer is option D because it cant be division or multiplication and minus does not work
Answer:
log 1/9 * log k
Step-by-step explanation:
[tex]\frac{1}{9} /k[/tex] = 1/9 * k/1 = 1/9 * k
plzz help with this question
Answer: 51 liters of fuel are required
Step by step: start by seeing how many times 476 can go into 1428
(1428/476=3)
Then take your sum of that and multiply it by 17 since that’s the number that correlates with 476
(17x3=51) therefore your answer is 51 liters
A company manufactures televisions. The average weight of the televisions is 5 pounds with a standard deviation of 0.1 pound. Assuming that the weights are normally distributed, what is the weight that separates the bottom 10% of weights from the top 90%?
Answer:
[tex]0.2564\text{ pounds}[/tex]
Step-by-step explanation:
The 90th percentile of a normally distributed curve occurs at 1.282 standard deviations. Similarly, the 10th percentile of a normally distributed curve occurs at -1.282 standard deviations.
To find the [tex]X[/tex] percentile for the television weights, use the formula:
[tex]X=\mu +k\sigma[/tex], where [tex]\mu[/tex] is the average of the set, [tex]k[/tex] is some constant relevant to the percentile you're finding, and [tex]\sigma[/tex] is one standard deviation.
As I mentioned previously, 90th percentile occurs at 1.282 standard deviations. The average of the set and one standard deviation is already given. Substitute [tex]\mu=5[/tex], [tex]k=1.282[/tex], and [tex]\sigma=0.1[/tex]:
[tex]X=5+(1.282)(0.1)=5.1282[/tex]
Therefore, the 90th percentile weight is 5.1282 pounds.
Repeat the process for calculating the 10th percentile weight:
[tex]X=5+(-1.282)(0.1)=4.8718[/tex]
The difference between these two weights is [tex]5.1282-4.8718=\boxed{0.2564\text{ pounds}}[/tex].
Answer:
0.2564
Step-by-step explanation:
90th percentile, we use the formula X=μ + Zσ,
Where u = mean and sigma = standard deviation and Z = 1.282
The mean is 5 and sigma = .1
X = 5+1.282(.1)
X = 5.1282
10th percentile, we use the formula X=μ + Zσ,
Where u = mean and sigma = standard deviation and Z = -1.282
The mean is 5 and sigma = .1
X = 5-1.282(.1)
X = 4.8718
The difference is
5.1282 - 4.8718
0.2564
Samples of rejuvenated mitochondria are mutated (defective) in 3% of cases. Suppose 13 samples are studied, and they can be considered to be independent for mutation. Determine the following probabilities.
(a) No samples are mutated.
(b) At most one sample is mutated.
(c) More than half the samples are mutated.
Round your answers to two decimal places (e.g. 98.76).
Answer:
a) 0.6730 = 67.30% probability that no samples are mutated.
b) 0.9436 = 94.36% probability that at most one sample is mutated.
c) 0% probability that more than half the samples are mutated.
Step-by-step explanation:
For each sample, there are only two possible outcomes. Either it is mutated, or it is not. The probability of a sample being mutated is independent of any other sample, 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.
Samples of rejuvenated mitochondria are mutated (defective) in 3% of cases.
This means that [tex]p = 0.03[/tex]
13 samples are studied
This means that [tex]n = 13[/tex]
(a) No samples are mutated.
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_{13,0}.(0.03)^{0}.(0.97)^{13} = 0.6730[/tex]
0.6730 = 67.30% probability that no samples are mutated.
(b) At most one sample is mutated.
This is:
[tex]P(X \leq 1) = P(X = 0) + P(X = 1)[/tex]
So
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 0) = C_{13,0}.(0.03)^{0}.(0.97)^{13} = 0.6730[/tex]
[tex]P(X = 1) = C_{13,1}.(0.03)^{1}.(0.97)^{12} = 0.2706[/tex]
Then
[tex]P(X \leq 1) = P(X = 0) + P(X = 1) = 0.6730 + 0.2706 = 0.9436[/tex]
0.9436 = 94.36% probability that at most one sample is mutated.
(c) More than half the samples are mutated.
This is:
[tex]P(X > 6.5) = P(X = 7) + P(X = 8) + P(X = 9) + P(X = 10) + P(X = 11) + P(X = 12) + P(X = 13)[/tex]
Then
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 7) = C_{13,7}.(0.03)^{7}.(0.97)^{6} \approx 0[/tex]
Using two decimal digits precision, all will be 0. So
0% probability that more than half the samples are mutated.
{1,4,5,6,7,8} {7} find the intersection
9514 1404 393
Answer:
{7}
Step-by-step explanation:
The only element common to both sets is 7. The intersection is {7}.
Which of the following is the most accurate statement about statistics?
a) We can absolutely be 100% certain in accurately generalizing the characteristics of entire population based on the sample data
b) By analyzing data, we may be able to identify connections and relationships in our data
c) We can explore in the midst of variation to better understand our data
d) limited data or experience likely generates less confidence
e) Non of the above
Answer:
b) By analyzing data, we may be able to identify connections and relationships in our data.
Step-by-step explanation:
In statistics decisions are based on probability sampling distributions. As statics is collection and analysis of data along with its interpretation and presentation.Use the figure to find x.
Answer:
[tex] x = 8.57[/tex]
Step-by-step explanation:
Here two triangles are given to us , which are attached to each other . Here we can use the concept of Trigonometry to find out the value of x. The angles of the triangle are 60° and 45° . Let the common side be p .
Step 1: Use the ratio of tan in upper triangle
[tex]\rm\implies tan60^o = \dfrac{perpendicular}{base} [/tex]
Substitute the respective values ,
[tex]\rm\implies \sqrt3=\dfrac{p}{7} [/tex]
Cross multiply ,
[tex]\rm\implies p = 7\sqrt3 [/tex]
Step 2: Use the ratio of cos in lower triangle
[tex]\rm\implies cos45^o = \dfrac{base}{hypontenuse} [/tex]
Substitute the respective values ,
[tex]\rm\implies \dfrac{1}{\sqrt2}=\dfrac{x}{7\sqrt3} [/tex]
Cross multiply ,
[tex]\rm\implies x= \dfrac{7\sqrt3}{\sqrt2} [/tex]
Put the approximate values of √2 and √3
[tex]\rm\implies x= \dfrac{7\times 1.732}{1.414} [/tex]
This equals to ,
[tex]\rm\implies \boxed{\blue{\rm \quad x = 8.57\quad}} [/tex]
Hence the value of x is 8.57 .
Answer:
The value of x is [tex]\frac{7\sqrt{6}}{2}[/tex]
Solution given:
AB=7
BD=x
<BAC=60°
<DBC=45°
In right angled triangle ABC
Tan 60°=opposite/adjacent
Tan 60°=BC/AB
Substitute value
[tex]\sqrt{3}[/tex]=[tex]\frac{BC}{7}[/tex]
BC=[tex]7\sqrt{3}[/tex]
again
againIn right angled triangle BCD
againIn right angled triangle BCDUsing Cos angle
Cos 45=adjacent/hypotenuse
Cos45°=BD/BC
Substituting value
[tex]\frac{\sqrt{2}}{2}=\frac{x}{7\sqrt{3}}[/tex]
Doing criss cross multiplication
[tex]\frac{\sqrt{2}}{2}*7\sqrt{3}=x[/tex]
x=[tex]\frac{7\sqrt{6}}{2}[/tex]
1289 +(-1236) + (2434) =
0 -1431
O 2345
O 2487
0 -1956
Answer:
This answer is 2487
which will be the third one
Hope this help
a site is 90m long and 45m wide what is the area of the site
Answer:4050m^2
Step-by-step explanation:
Assuming that the site is rectangular
Area= l x W
90 X 45
=4050
Answer:
1050m
How I got the answer: I assume the site is a rectangle so I'll use the formula for finding the area of a rectangle. Using the formula length times width I solved this problem. The length is 90m. The width is 45. When a question says x meters long it means the length is x meters. In other words long = length wide = width in a math problem. 90 times 40 is 1050m
Which of the following pairs of functions are inverses of each other?
O A. f(x) = 8x? - 10 and g(x) = x +10
8
B. f(x) = {+8 and g(x) = 2x - 8
O C. f(x) = 18 - 9 and g(x) =
O D. f(x) = 3x2 +16 and g(x) = -
18
X+9
16
Answer:
A is the answer I guess so...
The functions f(x) = 18/x -9 and g(x) = 18/x+9 are inverse to each other.
What is a function?A relation is a function if it has only One y-value for each x-value.
The given function f(x)= 18/x - 9
Let us replace f(x) by y
y=18/x - 9
Now x=18/y-9
Add 9 on both sides
x+9=18/y
Apply cross multiplication
y(x+9)=18
Divide both sides by x+9
y=18/(x+9)
f⁻¹(x)=18/(x+9)
Hence, the functions f(x) = 18/x -9 and g(x) = 18/x+9 are inverse to each other.
To learn more on Functions click:
https://brainly.com/question/30721594
#SPJ7
For 0 less than or equal to theta less than 2(pi), what are thebsolutions to sin↑2(theta)=2(sin↑2)(theta/2)?
I assume the up arrows are supposed to indicate exponents, so that the equation is
sin²(θ) = 2 sin²(θ/2)
Recall the half-angle identity for sine,
sin²(θ/2) = (1 - cos(θ))/2,
as well as the Pythagorean identity,
sin²(θ) + cos²(θ) = 1
Rewrite the equation in terms of cosine and solve:
1 - cos²(θ) = 1 - cos(θ)
cos²(θ) - cos(θ) = 0
cos(θ) (cos(θ) - 1) = 0
cos(θ) = 0 or cos(θ) - 1 = 0
cos(θ) = 0 or cos(θ) = 1
[θ = arccos(0) + 2nπ or θ = arccos(0) - π + 2nπ] or
… … … [θ = arccos(1) + 2nπ]
(where n is any integer)
[θ = π/2 + 2nπ or θ = -π/2 + 2nπ] or [θ = 2nπ]
In the interval 0 ≤ θ < 2π, we get the solutions θ = 0, π/2, and 3π/2.
(That is, for n = 0 in the first and third solution families, and n = 1 in the second family.)
Determine whether the following problem involves a permutation or combination. (It is not necessary to solve the problem.)
How many different -letter passwords can be formed from the letters S, T, U, W, X, Y, and Z if no repetition of letters is allowed?
The problem involves (combination or permiation) because the (order or number) of letters selected (does or does not) matter.
Answer:
Step-by-step explanation:
The order matters
stuwxyz is different than zyxwuts
You have 7 letters
The number of permutations is 7! which is 7*6*5*4*3*2*1 = 5040
Point P is plotted on the coordinate grid. If point S is 12 units to the left of point P, what are the coordinates of point S? On a coordinate grid from negative 12 to positive 12 in increments of 2, a point P is plotted at the ordered pair 6, negative 4. (6, −16) (−6, −16) (−6, −4) (6, 4)
9514 1404 393
Answer:
(−6, −4)
Step-by-step explanation:
Translating a point 12 units left subtracts 12 from its x-coordinate.
P(6, -4) +(-12, 0) = S(-6, -4)
An online retailer processed 60 merchandise return requests from Wyoming and Montana in a day. Return requests from Montana were 5 times as many as those from Wyoming. How many return requests were from Wyoming?
A) 10
B) 25
C) 15
D) 20
E) 5
The number of merchandise return requests for Wyoming is equal to 10.
Let merchandise return requests from Wyoming be W.
Let merchandise return requests from Montana be M.
Given the following data;
Total number of merchandise return requests for W and M = 60Translating the word problem into an algebraic equation, we have;
[tex]W + M = 60[/tex] .....equation 1
[tex]M = 5W[/tex] ......equation 2
To find the value of W, we would solve the system of equations by using the substitution method;
Substituting eqn 2 into eqn 1, we have;
[tex]W + 5W = 60\\\\6W = 60\\\\W = \frac{60}{6}[/tex]
Wyoming, W = 10 merchandise return requests.
Therefore, the number of merchandise return requests for Wyoming is equal to 10.
Find more information: https://brainly.com/question/8409825
How
many solutions are there to the equation below?
4(x - 5) = 3x + 7
A. One solution
B. No solution
O C. Infinitely many solutions
SUB
Answer:
A one solution
Step-by-step explanation:
4(x - 5) = 3x + 7
Distribute
4x - 20 = 3x+7
Subtract 3x from each side
4x-3x-20 = 3x+7-3x
x -20 = 7
Add 20 to each side
x -20+20 = 7+20
x = 27
There is one solution
Answer:
Step-by-step explanation:
Let's simplify that before we make the decision, shall we? We'll get rid of the parenthesis by distribution and then combine like terms.
4x - 20 = 3x + 7 and combining like terms and getting everything on one side of the equals sign:
1x - 27 = 0. Since that x has a power of 1 on it (linear), that means we have only 1 solution. If that was an x², we would have 2 solutions; if that was an x³, we would have 3 solutions, etc.
what is the quotient 3/8 ÷5/12
Answer:
9/10
Step-by-step explanation:
3/8 ÷5/12
Copy dot flip
3/8 * 12/5
Rewriting
3/5 * 12/8
3/5 * 3/2
9/10
Can somebody help me to solve this?
Answer:
B
Step-by-step explanation:
Given
[tex]\sqrt{ab}[/tex] = [tex]\sqrt{bc}[/tex] ( square both sides )
ab = bc ( divide both sides by b ) , then
a = c
Given
[tex]\sqrt{ac}[/tex] = [tex]\sqrt{4c^4}[/tex] ( square both sides )
ac = 4[tex]c^{4}[/tex] ( but a = c) , so
4[tex]c^{4}[/tex] = c² ( subtract c² from both sides )
4[tex]c^{4}[/tex] - c² = 0 ← factor out c² from each term on the left side
c²(4c² - 1) = 0 ← 4c² - 1 is a difference of squares
c²(2c - 1)(2c + 1) = 0
Equate each factor to zero and solve for x
c² = 0 ⇒ c = 0
2c - 1 = 0 ⇒ 2c = 1 ⇒ c = [tex]\frac{1}{2}[/tex]
2c + 1 = 0 ⇒ 2c = - 1 ⇒ c = - [tex]\frac{1}{2}[/tex]
But c > 0 , then c = [tex]\frac{1}{2}[/tex] → B