Answer:
B and C
Step-by-step explanation:
but i'm not sure
The Federal Reserve System publishes data on family income based on its Survey of Consumer Finances. When the head of the household has a college degree, the mean before-tax family income is $ 85,050. Suppose that 56% of the before-tax family incomes when the head of the household has a college degree are between $75,000 and $95,100 and that these incomes are normally distributed. What is the standard deviation of before-tax family incomes when the head of the household has a college degree
Answer:
The standard deviation is $13,052.
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 zscore 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 pvalue, we get the probability that the value of the measure is greater than X.
When the head of the household has a college degree, the mean before-tax family income is $ 85,050.
This means that [tex]\mu = 85,050[/tex]
Suppose that 56% of the before-tax family incomes when the head of the household has a college degree are between $75,000 and $95,100 and that these incomes are normally distributed.
They are equally as far from the mean, one above, and one below. This means that when [tex]X = 95100[/tex], Z has a pvalue of 0.5 + (0.56/2) = 0.78. So when X = 95100, Z = 0.77. We use this to find [tex]\sigma[/tex].
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]0.77 = \frac{95100 - 85050}{\sigma}[/tex]
[tex]0.77\sigma = 10050[/tex]
[tex]\sigma = \frac{10050}{0.77}[/tex]
[tex]\sigma = 13052[/tex]
The standard deviation is $13,052.
giving brainliest *easy*
I’ve been at these questions all day. Please help
Answer:
தமிழ்நாட்டில் உள்ள நெல் வகைகளை குறிப்பிட்டு எழுதுக
Answer:
How does the novel "In Cold Blood" address the question of responsibility regarding the Clutter murders?
Calculate the volume of this triangular prism?
Answer:
960 sq cm
Step-by-step explanation:
(16*12*10)/2
What is the product of (x - 5) and (x - 4)? Use the model to find the result.
Answer:
x2 - 9x +20
Step-by-step explanation:
can yall help please
Step-by-step explanation:
I think your answer will be 15
What is the value of x in the equation shown? -4 = 5x + 3 A) -3 4/5.
B) -1 2/5
C) 1/5
D) 1 2/5
Answer:
B
Step-by-step explanation:
60 divided by 4 - 3^2 + 2 (5)
Answer:
16
Step-by-step explanation:
Answer:
16
Step-by-step explanation:
First Step: Solve the exponent 3^2=9
Then, you get 60 divided by 4-9+2(5)
Then, you do Multiplication and Division from left to right, so 60/4=15, 2(5)=10
Then, you get 15-9+10
Then, you do addition and subtraction from left to right.
15-9=6, then 6+10=16
Please help me with this
WHAT'S 675 DIVIDED BY 8 HELPPPP PLEASE TELL ME THE NUMBERS TO SHOW MY WORK
Answer:
85.625 is the answer
Step-by-step explanation:
or, 85 whole 5/675
Yoonie is a personnel manager in a large corporation. Each month she must review 16 of the employees. From past experience, she has found that the reviews take her approximately four hours each to do with a population standard deviation of 1.2 hours. Let X be the random variable representing the time it takes her to complete one review. Assume X is normally distributed. Let X be the random variable representing the mean time to complete the 16 reviews. Assume that the 16 reviews represent a random set of reviews. Complete the distributions.
A. Find the probability that the mean of a month’s reviews will take Yoonie from 3.5 to 4.25 hrs.
B. P(_____) = _______.
C. Find the 95th percentile for the mean time to complete one month's reviews.
D.The 95th Percentile =________.
Answer:
a) [tex]P(3.5 \leq X \leq 4.25) = 0.7492[/tex]
b) The 95th percentile is 4.4935 hours.
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
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 zscore 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 pvalue, we get the probability that the value of the measure is greater than X.
Central Limit Theorem
The Central Limit Theorem estabilishes 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.
The reviews take her approximately four hours each to do with a population standard deviation of 1.2 hours.
This means that [tex]\mu = 4, \sigma = 1.2[/tex]
16 reviews.
This means that [tex]n = 16, s = \frac{1.2}{\sqrt{16}} = 0.3[/tex]
A. Find the probability that the mean of a month’s reviews will take Yoonie from 3.5 to 4.25 hrs.
This is the pvalue of Z when X = 4.25 subtracted by the pvalue of Z when X = 3.5. So
X = 4.25
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{4.25 - 4}{0.3}[/tex]
[tex]Z = 0.83[/tex]
[tex]Z = 0.83[/tex] has a pvalue of 0.7967
X = 3.5
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{3.5 - 4}{0.3}[/tex]
[tex]Z = -1.67[/tex]
[tex]Z = -1.67[/tex] has a pvalue of 0.0475
0.7967 - 0.0475 = 0.7492
So
[tex]P(3.5 \leq X \leq 4.25) = 0.7492[/tex]
C. Find the 95th percentile for the mean time to complete one month's reviews.
This is X when Z has a pvalue of 0.95, so X when Z = 1.645.
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]1.645 = \frac{X - 4}{0.3}[/tex]
[tex]X - 4 = 0.3*1.645[/tex]
[tex]X = 4.4935[/tex]
The 95th percentile is 4.4935 hours.
(8x + 11x) + (-7 - 18)
Answer:
19x - 25
steps:
(8x + 11x) + (-7 - 18)
19x + (-25)
positive x negative = negative
19x - 25
Answer:
19x - 25
Step-by-step explanation:
(8x + 11x) + (-7 - 18) <------- add the bold ones (combine like terms)...
19x + (-7 - 18) <--------------- subtract the bold ones...
(19x) - 25 <-------------------- eliminate parenthases
19x - 25 <--------------------- solution...
as a medical technician, Stephanie has been offered a job that pays $53 000.00 per year and another job that pays $25.50 per hour. assuming a 40 hour work week and all other conditions being the same, at which job will she earn more?
Answer:
25.50x40= 1020/ week
times 52 weeks- $53040
WILL GIVE BRAINLIST PLS HELP Find z. Just write the number. Answer should be a whole number.
Answer:
8
Step by Step Explanation
Answer and Step-by-step explanation:
To find Z, we have to use the trigonometric function of Sine.
The Sine trig function looks like this:
sin(Angle) = [tex]= \frac{opposite.side}{hypotenuse}[/tex]
Plug in the values and solve for z.
[tex]sin(30) = \frac{4}{z} \\\\\\\\\\z = \frac{4}{sin(30)}[/tex]
Plug into a calculator and solve.
We get z to be 8.
#teamtrees #PAW (Plant And Water)
Write each product using an exponent. 9 x 9 x 9 x 9 x9
(Will be giving brainliest)
Answer: 9^ 5
Step-by-step explanation: since there is 5 9’s multiplied by each other, it would be 9 to the 5th power.
[tex]\huge\text{Hey there!}[/tex]
[tex]\mathtt{9\times9\times9\times9\times9}\\\mathtt{= 81\times 81\times9}\\\mathtt{= 6,561\times9}\\\mathtt{= 59,049}\\\mathtt{= 9\times 9\times 9 \times 9 \times 9 \rightarrow 9^5}[/tex]
[tex]\huge\text{Therefore your answer should be:}[/tex]
[tex]\huge\boxed{\mathtt{9^5}}\huge\checkmark[/tex]
[tex]\huge\boxed{\mathtt{Good \ luck \ on \ your \ assignment\ \& \ enjoy}}\\\huge\boxed{\mathtt{your \ day!}}[/tex]
An elevator has a placard stating that the maximum capacity is 1580 lb-10 passengers. So, 10 adult male passengers can have a mean weight of up to 1580/10 = 158 pounds. If the elevator is loaded with 10 adult male passengers, find the probability that it is overloaded because they have a mean weight greater than 158 lb. (Assume that weights of males are normally distributed with a mean of 160 lb and a standard deviation of 35 lb.) Does this elevator appear to be safe?
Answer:
a) 0.5714 = 57.14% probability that it is overloaded because they have a mean weight greater than 158 lb
b) No, because the probability of being overloaded is considerably high(57.14%). Ideally, it should be under 5%, which would be considered an unusual event.
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
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 zscore 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 pvalue, we get the probability that the value of the measure is greater than X.
Central Limit Theorem
The Central Limit Theorem estabilishes 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.
Assume that weights of males are normally distributed with a mean of 160 lb and a standard deviation of 35 lb.
This means that [tex]\mu = 160, \sigma = 35[/tex]
Sample of 10:
This means that [tex]n = 10, s = \frac{35}{\sqrt{10}} = 11.07[/tex]
a) Find the probability that it is overloaded because they have a mean weight greater than 158 lb.
This is 1 subtracted by the pvalue of Z when X = 158. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{158 - 160}{11.07}[/tex]
[tex]Z = -0.18[/tex]
[tex]Z = -0.18[/tex] has a pvalue of 0.4286
1 - 0.4286 = 0.5714
0.5714 = 57.14% probability that it is overloaded because they have a mean weight greater than 158 lb.
b.) Does this elevator appear to be safe?
No, because the probability of being overloaded is considerably high(57.14%). Ideally, it should be under 5%, which would be considered an unusual event.
Plzzz someone help me
I NEED HELP ASAP!!!!!!!!!
Answer:
a=81.0
there ya go
Show that sin( + 180°) + 2 cos( − 360°) − sin( − 180°) = 2x
Answer:
Example 1: Change sin 80° cos 130° + cos 80° sin 130° into a trigonometric function in ... Example 2: Verify that cos (180° − x) = − cos x ... Example 7: Verify that sin (360° − x) = − sin x.
Fred and Ted are interested in the average height of NC State students. They randomly sample students from NC State and construct confidence intervals from their data. Fred sampled 121 students to construct his confidence interval. Ted sampled 144 students to construct his confidence interval; both create histograms for their data which have symmetric, unimodal, and roughly bell-shaped distributions. Which of the following is true about the margins of error for these experiments?
a. Fred's margin of error is larger than Ted's.
b. Ted's margin of error is larger than Fred's.
c. Fred and Ted have the same size margins of error.
d. We are unable to determine which margin of error is larger without knowing more about Fred and Ted's samples.
Answer:
a. Fred's margin of error is larger than Ted's.
Step-by-step explanation:
Margin of error of a confidence interval:
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
In which z is related to the confidence level(the higher the confidence level the larger the value of z) [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
From this, we have that:
A higher confidence level leads to a larger margin of error.
A larger sample size leads to a smaller margin of error.
In this question:
Same confidence level.
Fred's sample is smaller, so his margin of error will be larger.
The correct answer is given by option a.
For the same confidence level, Fred's sample is smaller, so hir margin of error will be larger. The correct option is A.
What is normal a distribution?It is also called the Gaussian Distribution. It is the most important continuous probability distribution. The curve looks like a bell, so it is also called a bell curve.
Fred and Ted are interested in the average height of NC State students.
They randomly sample students from NC State and construct confidence intervals from their data.
Fred sampled 121 students to construct his confidence interval.
Ted sampled 144 students to construct his confidence interval.
The margin of error of a confidence interval
[tex]\rm M =z \dfrac{\sigma }{\sqrt{n}}[/tex]
Where z is related to the confidence level, [tex]\sigma[/tex] is the standard deviation level and n is a sample size.
By the formula, we have
A higher confidence level leads to a larger margin of error.
A larger sample size leads to a small margin of error.
For the same confidence level, Fred's sample is smaller, so hir margin of error will be larger. The correct option is A.
More about the normal distribution link is given below.
https://brainly.com/question/12421652
Alice and Finn roll two number cubes. Which of the following rules will make the game fair?
A) Alice wins if a total of 5 is rolled. Finn wins if a total of 9 is rolled.
B) Alice wins if a total of 7 is rolled. Finn wins if a total of 8 is rolled.
C) Alice wins if a total of 3 is rolled. Finn wins if a total of 10 is rolled.
D) Alice wins if a total of 4 is rolled. Finn wins if a total of 11 is rolled.
Answer:
Alice wins if a total of 4 is rolled. Finn wins if a total of 11 is rolled.
(9z+7) whats the value of z
Answer:
-0.78
Step-by-step explanation:
9z+7
9z = -7
z = -7÷9
z = -0.78
A football team has 5 freshman, 8 sophomores, 11 juniors, and 16 seniors. If two are chosen at random to participate in the coin toss, what is the probability that both players chosen will be seniors?
Answer:
The probability percentage that both players will be seniors is 15.38%.
Step-by-step explanation:
Given that a football team has 5 freshman, 8 sophomores, 11 juniors, and 16 seniors, if two are chosen at random to participate in the coin toss, to determine what is the probability that both players chosen will be seniors the following calculation must be done:
5 + 8 + 11 + 16 = 40
16/40 = X
4/10 = X
0.4 = X
15/39 = X
5/13 = X
0.38 = X
0.4 x 0.38 = X
0.1538 = X
Thus, the probability percentage that both players will be seniors is 15.38%.
Please help me with this
73
Step-by-step explanation:
I think that this is an isosceles triangle, and like since ST=SR
Therefore, m(<T) = m(<R)= 73
pretty difficult for me at least
Answer:
Sales tax = $1.25
Total = $25+$1.25 = $26.25
Step-by-step explanation:
Tax = 0.05 x 25 = 1.25
Total = 1.25 + 25
Answer:
To calculate tip or tax, simply move the decimal place 2 to the right and multiply it by the price. For example, If you want to leave a 20% tip, multiply the cost by 0.20 to get the tip amount or multiply the cost by 1.20 to get the total
The sales tax is $1.25
The total price is $26.25
What is the distance between (-2, -3) and (-4, 3)? Use the distance formula and show your work.
Answer:
D = 6.32
Step-by-step explanation:
-2 to -4 = 2
-3 to 3 = 6
D² = 2² + 6²
D² = 4 + 36 = 40
D = 6.32
Helppppppppppppppppp
Answer:
3. y = -⅕x - 5
Step-by-step explanation:
The equation of straight line is given by the formula, y = mx + c
Where;
m is the slope.
x and y are the points.
c is the intercept.
Given the standard form equation;
x + 5y = -25
Rearranging the equation, we have;
5y = -x - 25
Dividing all through by 5, we have;
y = -⅕x - 5
Pete painted 4/5 of a rectangle green. He painted 1/8 of the same rectangle blue. Pete painted the rest the rectangle red. What fraction of the rectangle did Pete paint red? please explain!
Answer:
Step-by-zbastep explanation:
Find the volumes of the solids generated by revolving the regions bounded by the graphs of the equations about the given lines.
y = root x
y = 0
x = 3
the x-axis
the y-axis
the line x = 3
the line x = 6
Answer:
x-axis = [tex]\frac{9\pi }{2}[/tex]
y-axis = [tex]\frac{4\pi }{5} .3(^{\frac{5}{2} } )[/tex]
Line x =3 : [tex]\frac{44\sqrt{3} }{5} \pi[/tex]
Line x = 6 : [tex]\frac{84\sqrt{3}\pi }{5}[/tex]
Step-by-step explanation:
Given lines : y = √x
y = 0
x = 3
To determine the volumes generated we will use the disk method for each of the lines,
attached below is the detailed solution for line x =3 , same procedure will be repeated for each value of x and y to obtain the given results
The volume generated ( x axis )
= [tex]\frac{9\pi }{2}[/tex]
volume generated ( y _axis )
= [tex]\frac{4\pi }{5} .3(^{\frac{5}{2} } )[/tex]
Volume about x = 3
= [tex]\frac{44\sqrt{3}\pi }{5}[/tex]
Volume about x = 6
= [tex]\frac{84\sqrt{3}\pi }{5}[/tex]
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Seventh grade
> L.8 Solve percent equations: word problems JS6
You have prizes to reveal!
Learn with an example
The city council voted on a new tax. 27 council members voted in favor of the tax. The
council has 90 members. What percentage of the council members voted in favor of the tax?
Write your answer using a percent sign (%).
Submit
Answer:
Step-by-step explanation:
27 ÷ 90 = 0.3 = 0.30 = 30%