Answer:
d
Step-by-step explanation:
61-1/2=30
30-4=26
solve each system.
y=7-3x
3x+y=10
Answer: 0 = 3
Step-by-step explanation: If y = 7 - 3x, we can plug that in for y in the equation 3x + y = 10 by writing it as 3x + 7 - 3x = 10.
- 7 - 7
--------------------------
3x - 3x = 3
0 = 3
A manufacturer of all-in-one printers is concerned that the warranty costs for a particular printer model exceed the amount expected by the company. Based on a review of completed warranty claims, the distribution of the warranty cost per claim is skewed to the right with mean $150 and standard deviation $50. A random sample of 25 completed warranty claims is selected, and the sample mean cost is recorded. Suppose the process of selecting a random sample of 25 completed warranty claims and recording the sample mean cost is repeated for a total of 100 samples. Which of the following best describes a dotplot created from the 100 sample means?
(A) The dotplot has the same shape as the distribution of the population with mean $150 and standard deviation $25.
(B) The dotplot has the same shape as the distribution of the population with mean $150 and standard deviation $50.
(C) The dotplot has the same shape as the distribution of the population with mean $150 and standard deviation $100.
(D) The dotplot is closer to approximately normal than the distribution of the population with mean $150 and standard deviation $10.
(E) The dotplot is closer to approximately normal than the distribution of the population with mean $150 and standard deviation $50.
Answer: D. The dotplot is closer to approximately normal than the distribution of the population with mean $150 and standard deviation $10.
Step-by-step explanation:
Based on the dotplot created from the 100 sample, the dotplot is closer to approximately normal than the distribution of the population with mean $150 and standard deviation $10.
The mean of the sampling distribution is just exactly like the population mean. On the other hand, the standard deviation will be: = 50/✓25 = 50/5 = 10
Therefore, the correct option is D.
Solve for X
Pls help
Answer:
xxxtentacion=6&20
Step-by-step explanation:
Answer:
12
Step-by-step explanation:
The sum of any two intieior angles in a triangle equal to the opposite angle.
So 30 + 5X + 15 = 9X - 3
Solving for X
48 = 4X
X = 12
One fifth of the animals at the shelter are stray cats. If there are 13 stray cats at the shelter, how many animals are there in total?
Answer:
1/5 x X = 13
x5 x5
x = 65 in total
how much will a person pay for 1.5 pounds of bananas at a price of .95 per pound
Answer:
1.425
Step-by-step explanation:
when 1pound is 0.95
then 1.5should be multiplied by 0.95
The function h(t) = - 16t2 + 48t + 160 can be used to model the height, in feet, of an object t
seconds after it is launched from the top of a building that is 160 feet tall.
Two other forms of the function are:
h(t) = -16(t - 5)(t+2)
h(t) = -16(t-1.5)2 +196
Which value of the function represents the maximum height of the object?
A h(0)
B. h(1.5)
C. h(2)
D. h(5)
Answer:
answer is c because you have to put in the 2 and get -16
Because of safety considerations, in May 2003 the Federal Aviation Administration (FAA) changed its guidelines for how small commuter airlines must estimate passenger weights. Under the old rule, airlines used 180 pounds as a typical passenger weight (including carry-on luggage) in warm months and 185 pounds as a typical weight in cold months. The Alaska Journal of Commerce (May 25, 2003) reported that Frontier Airlines conducted a study to estimate average passenger plus carry-on weights. They found an average summer weight of 183 pounds and a winter average of 190 pounds. Suppose that each of these estimates was based on a random sample of 100 passengers and that the sample standard deviations were 20 pounds for the summer weights and 23 pounds for the winter weights.
Required:
a. Construct and interpret a 95% confidence interval for the mean summer weight (including carry-on luggage) of Frontier Airlines passengers.
b. Construct and interpret a 95% confidence interval for the mean winter weight (including carry-on luggage) of Frontier Airlines passengers.
c. The new FAA recommendations are 190 pounds for summer and 195 pounds for winter. Comment on these recommendations in light of the confidence interval estimates from Parts (a) and (b).
Answer:
a) The 95% confidence interval for the mean summer weight (including carry-on luggage) of Frontier Airlines passengers is between 179 and 187 pounds. This means that we are 95% sure that the mean summer weight of all Frontier Airlines passengers is between these two values.
b)
The 95% confidence interval for the mean winter weight (including carry-on luggage) of Frontier Airlines passengers is between 185.4 pounds and 194.6 pounds. This means that we are 95% sure that the mean winter weight of all Frontier Airlines passengers is between these two values.
c) They are respected, as the upper bound of both intervals is below the new FAA recommendations.
Step-by-step explanation:
We have the standard deviation for the sample, which means that the t-distribution is used to solve these questions.
Question a:
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 100 - 1 = 99
95% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 99 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.95}{2} = 0.975[/tex]. So we have T = 1.9842
The margin of error is:
[tex]M = T\frac{s}{\sqrt{n}} = 1.9842\frac{20}{\sqrt{100}} = 4[/tex]
In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 183 - 4 = 179 pounds.
The upper end of the interval is the sample mean added to M. So it is 183 + 4 = 187 pounds.
The 95% confidence interval for the mean summer weight (including carry-on luggage) of Frontier Airlines passengers is between 179 and 187 pounds. This means that we are 95% sure that the mean summer weight of all Frontier Airlines passengers is between these two values.
Question b:
Critical value is the same(same sample size and confidence level).
The margin of error is:
[tex]M = T\frac{s}{\sqrt{n}} = 1.9842\frac{23}{\sqrt{100}} = 4.6[/tex]
The lower end of the interval is the sample mean subtracted by M. So it is 190 - 4.6 = 185.4 pounds.
The upper end of the interval is the sample mean added to M. So it is 190 + 4.6 = 194.6 pounds.
The 95% confidence interval for the mean winter weight (including carry-on luggage) of Frontier Airlines passengers is between 185.4 pounds and 194.6 pounds. This means that we are 95% sure that the mean winter weight of all Frontier Airlines passengers is between these two values.
c. The new FAA recommendations are 190 pounds for summer and 195 pounds for winter. Comment on these recommendations in light of the confidence interval estimates from Parts (a) and (b).
They are respected, as the upper bound of both intervals is below the new FAA recommendations.
Construct and interpret a 95% confidence interval to estimate the proportion of the earth that is water. Show all work. Make sure to check your conditions and state your conclusion.
1.) Randomly selected
2.) Less than 10% of population
3.) 50 (0.68)
50 (0.32)
the answer would be 2
what is 24.40% 37.60% 7/25 and 3/10 ordered from least to greatest
Answer:
7/25,3/10, 24.40%,37.60%
PLEASE HELP!
a-b+c=3
a+b+c=7
Find b.
A) 1
B) 2
C) 3
D) 4
E) 5
Answer:
b
Step-by-step explanation:
I think the day of my birthday was a little more aware of my own life than the poem I think I c I
Answer:
B
Step-by-step explanation:
Given the 2 equations
a - b + c = 3 → (1)
a + b + c = 7 → (2)
Subtract (1) from (2) term by term to eliminate a and c
a - a + b - (- b) + c - c = 7 - 3 , that is
0 + b + b + 0 = 4
2b = 4 ( divide both sides by 2 )
b = 2 → B
Please help with this math problem if You don’t give me a file link I will mark you brainlist!!
WXYZ is dilated by a scale factor of 3. The length of W'X'Y'Z' is ____
units, and the width is____
units.
Answer:
18, 12
Step-by-step explanation:
Assuming this is follow-up from the previous question you asked? If not, I apologize for misunderstanding.
Dilation factor by 3 is bigger than 1 = Expansion
Originally 6, 4
6*3 = 18
4*3 = 12
Answer:
18,12
Step-by-step explanation:
W (1, -2), X (7,-2), Y (7,-6), and Z (1, -6).
To dilate the shape, multiply it's coordinates by the scale factor.
W'(3,-6), X'(21,-6), Y'(21,-18), Z(3, -18)
The distance formula: [tex]d=\sqrt{(x_1-x_2)^2+(y_1-y_2)^2}[/tex]
plug W'(3,-6) and X'(21,-6) in to get the length
[tex]\sqrt{(3-21)^2+(-6-(-6))^2}=\sqrt{(-18)^2 +0^2}=\sqrt{324} =18[/tex]
plug X(21,-6) and Y(21,-18) to get the width
[tex]\sqrt{(7-7)^2+(-2-(-6))^2}=\sqrt{0^2 +4^2}=\sqrt{16} =4[/tex]
[tex]\sqrt{(21-21)^2+(-6-(-18))^2}=\sqrt{0^2 +12^2}=\sqrt{144} =12[/tex]
How do you know how to set up a equation?
Answer:
Basic Steps to Setting Up Equations
-Determine what the question is asking.
-Write down the relevant information in simple statements.
-Assign symbols to unknown values that need to be found.
-Determine how the statements relate to each other mathematically.
Solving Story Problems
Story problems can contain lots of information, including details that are not necessary to solve the problem. Additionally, the problem may assume general knowledge on the reader's part, and not explain all the information explicitly. Writing that information down in a streamlined form is an efficient way to solve problems.
Step-by-step explanation:
If g(x) = 4x - 9. solve g[g(x)] = g(x) for x.
Answer:
f ( x + 4 /9 ) = 4 x − 65/ 9
Step-by-step explanation:
PLEASE HELP!! I will give brainiest !!!
Answer:
no f-ing clue
Step-by-step explanation:
What is the y-intercept for 6x - 2y = 15
Answer:
-2y=-6x+15
2y=6x-15
y=3x-7.5
y intercept is 7.5
Step-by-step explanation:
make y the subject
Ralph’s shirt company sells t-shirts for $7.50 each with a flat rate of $10 for shipping. Frank’s t-shirt company sells t-shirts for $10 each with free shipping.
A: Write an equation to represent each T-Shirt company.
Ralph's:_______________
Frank's:_______________
B: Solve the system of equations by using the graph.
C: What does the solution mean in the context of the solution?
Answer:
A: Ralph y = 10 + 7.50x
Frank y = 10x
B: x = 4, y = 40
C: x = 4 means that in order for the companies to make the same amount of money, they have to sell 4 shirts each. When the companies sell 4 shirts (or multiples of 4) they are making the same amount of money.
Step-by-step explanation:
Because both equations are equal to y, set them equal to each other.
10x = 10 + 7.50x
2.5x = 10
x = 4
Plug in x to a y equation.
y = 10(4)
y = 40
18. The temperature was
40° at noon. At midnight the
temperature was -10°.
Which integer describes the
change in temperature?
Answer:
Step-by-step explanation: Find the number between 40 and -10.
start at 40 and end at -10.
-40=0
0-10=-10
the tempature changed by 50 degrees.
Researchers at the National Cancer Institute released the results of a study that investigated the effect of weed-killing herbicides on house pets. The randomly sampled 400 dogs from homes where an herbicide was used on a regular basis, diagnosing lymphoma in 230 of them. Of 200 dogs randomly sampled from homes where no herbicides were used, only 25 were found to have lymphoma. For this problem, let p1 be the population proportion of dogs that get lymphoma from homes where herbicides are used and p2 be the population proportion of dogs that get lymphoma from homes where herbicides are not used. Researchers are interested in learning about the difference in the proportion of cancer diagnoses between the two groups. What is the 95% confidence interval for the difference in the proportion of cancer diagnoses between the two groups
Answer:
The 95% confidence interval for the difference in the proportion of cancer diagnoses between the two groups is (0.3834, 0.5166).
Step-by-step explanation:
Before building the confidence interval, we need to understand the central limit theorem and subtraction between normal variables.
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.
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]
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.
The randomly sampled 400 dogs from homes where an herbicide was used on a regular basis, diagnosing lymphoma in 230 of them.
This means that:
[tex]p_h = \frac{230}{400} = 0.575, s_h = \sqrt{\frac{0.575*0.425}{400}} = 0.0247[/tex]
Of 200 dogs randomly sampled from homes where no herbicides were used, only 25 were found to have lymphoma.
This means that:
[tex]p_n = \frac{25}{200} = 0.125, s_n = \sqrt{\frac{0.125*0.875}{200}} = 0.0234[/tex]
Distribution of the difference:
[tex]p = p_h - p_n = 0.575 - 0.125 = 0.45[/tex]
[tex]s = \sqrt{s_h^2+s_n^2} = \sqrt{0.0247^2 + 0.0234^2} = 0.034[/tex]
Confidence interval:
The confidence interval is:
[tex]p \pm zs[/tex]
In which
z is the zscore that has a pvalue 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 pvalue of [tex]1 - \frac{0.05}{2} = 0.975[/tex], so [tex]Z = 1.96[/tex].
The lower bound is [tex]0.45 - 1.96(0.034) = 0.3834[/tex]
The upper bound is [tex]0.45 + 1.96(0.034) = 0.5166[/tex]
The 95% confidence interval for the difference in the proportion of cancer diagnoses between the two groups is (0.3834, 0.5166).
Maya is a plumbing engineer who works with Overflo clients on residential plumbing and field draining and irrigation projects. Overflo closely supervises all of its engineers, and dictates their work schedules. Noel works part-time in the evenings cleaning the offices and warehouse. To Noel is Overflo's:_____.
a. employee, agent and independent contractor.
b. employee and agent.
c. agent to Overflo's customers.
d. independent contractor only.
what is the volume of a prism if the width is 8 the height is 6 and the length is 4
Answer: 48
Step-by-step explanation:
V = b x h
V = 8 x 6
V = 48
Original price of concert tickets: $101.00
Markup: 21%
What's the selling price of the concert tickets?
Answer:
122.21
Step-by-step explanation:
So our orginal value is 101 dollars,
Markup is increase in value.
The markup in this problem is 21%
We can thikn of this as 121%.
So to find the markup price, we must multiply 121% by 101.
We can thibk of 121% being myltiplying by 101 as:
1.21*101
This will get you:
122.21
So this is your answer!
Hope this helps! :)
Examine the rotation. Which best describes point D?
Find the equation of the exponential function represented by the table below: 1 4 16 64
(khan academy) please help
Answer: C
Step-by-step explanation:
[tex](2^{-7} \cdot 5^5)^2\\\\=2^{(-7)(2)} \cdot 5^{(5)(2)}\\\\=2^{-14} \cdot 5^{10}[/tex]
Rahul performed an experiment using 16 windup rubber band single-propeller airplanes. He wound up the propeller a different number of times and recorded the amount of time (in seconds) that the airplane flew for each number of rotations that the propeller was wound. A regression analysis was performed and the partial computer output is given below.
The regression equation is
Time = 0.924 + 0.0462 Rotations
Predictor Coef SE Coef T P
Constant 0.9241 0.6413 1.44 0.172
Rotation 0.04625 0.01565 2.96 0.010
S= 0.5426 ; R-Sq= 38.4% ; R -Sq(adj) =34.0%
Required:
What is a 95 percent confidence interval for the slope of the regression line that relates the number of rotations the rubber band is wound and the plane's flight time?
Answer:
0.0462 ± 2.131(0.01565)
Step-by-step explanation:
The confidence interval for the slope, :
Slope Coefficient = 0.0462
Slope Coefficient ± Margin of error
Margin of Error = Tcritical * standard error
Standard Error (rotation) = 0.01565
We use T distribution, because sample size is small ; n = 16
Tcritical at 95% ; df = n - 1 = 16 - 1 = 15
Tcritical(0.05, 15) = 2.131
Hence,
Margin of Error = 2.131(0.01565)
Slope Coefficient for rotation = 0.0462
95% Confidence interval :
0.0462 ± 2.131(0.01565)
The 95% confidence interval for the slope of the regression line is 0.0462 ± 0.0333 or (0.01284, 0.07955)
What is the margin of error?The probability or the chances of error while choosing or calculating a sample in a survey is called the margin of error.
Slope coefficient = 0.0462
Slope coefficient ± Margin of error
The margin of error will be given as
[tex]\rm Margin \ of \ error = T_{critical} \times standard \ error[/tex]
Standard error = 0.01565
We use T distribution because the sample size is small
[tex]\rm n = 16 \\\\T_{critical} \ at \ 95\% \ ; df = n-1 = 16- 1 = 15\\\\T_{critical} \ (0.05, 15) = 2.131[/tex]
Then we have
Margin of error = 2.131 × 0.01565
Margin of error = 0.0333
Then the 95% confidence interval will be
0.0462 ± 0.0333
More about the margin of error link is given below.
https://brainly.com/question/6979326
Write each as a decimal. State whether the decimal is repeating or terminating (1-7)
Write each decimal as a fraction (8-14)
No. 4 and 7 are mixed fractions
Answer:
0.625
0.035
etc.
Step-by-step explanation:
You just have to type the fraction in the calculator
the width of a rectangle is 2 m less than the length. if the area of the rectangle is 48sq meters. what is the length and width
I am lost and need help asap!
Answer:
<CED = 58°
Step-by-step explanation:
Let <CED = x
We can obtain the value of x as illustrated below:
<CED + 122 = 180 (angles on a straight line)
x + 122 = 180
Collect like terms
x = 180 – 122
x = 58°
<CED = x
x = 58°
Thus,
<CED = 58°
A pizza with a radius of 9 inches is sliced into 12 pieces. What is the length of the crust of one piece of pizza?
Answer:
21.2058333333
Step-by-step explanation:
Answer:
Step-by-step explanation:
Circumference = 2 * pi * r
r = 9 inches
Circumference = 18 pi
If there are 12 pieces (all equal) then the length of the crust is
C_part = 18*pi/12
C_part = 3/2 * pi
C_part= 4.71 inches
Solve the equation.
3(x−9)=30
Answer:
x = 19
Step-by-step explanation:
3(x - 9) = 30
Divide both sides by 3 to isolate the binomial.
x - 9 = 10
Add 9 to both sides to isolate x.
x = 19
Check your answer by plugging x = 19 back into the equation.
3(x - 9) = 30
3(19 - 9) = 30
Subtract.
3(10) = 30
Multiply.
30 = 30
Your answer is correct.
Hope this helps!
Answer:
x = 19
Step-by-step explanation:
First, we must distribute 3(x-9) = 30
[tex]3x - 27 = 30[/tex]
Now, that we've distributed this equation, we can proceed.
Secondly, since there is a subtraction sign in front of 27, we must do the opposite, addition.
Add 27 to 27 and 30:
[tex]3x - 27 = 30[/tex]
[tex]-27 + 27 = 0[/tex]
[tex]30 + 27 = 57[/tex]
Furthermore, -27 + 27 is 0, so it cancels itself out. Also, since we added 30 and 27 and got 57, replace 30 with 57.
[tex]3x = 57[/tex]
Lastly, divide 57 by the number in front of coefficient, 3.
[tex]57/3=19[/tex]
Therefore, [tex]x=19.[/tex]
**TO MAKE THIS MORE UNDERSTANDING, THIS IS HOW YOUR EQUATION SHOULD LOOK WHILE SOLVING**