Write the equation of the line that goes through the point (-4,7) and has a slope of -5.
Answer:
y= -5x-13
Step-by-step explanation:
start with the linear equation
y= mx+b
indentify what you already have.
x= -4 and y= 7 and m(slope)= -5
We are solving for b, so plug in what you have.
7= -5(-4)+b
Simplify.
7= 20+b
Subtract 20 on both sides.
-13= b
Rewrite your equation with the x and y values.
y= -5x-13
The mean salary of people living in a certain city is $37,500 with a standard deviation of $2,119. A sample of n people will be selected at random from those living in the city. Find the smallest sample size n that will guarantee at least a 90% chance of the sample mean income being within $500 of the population mean income.
Answer:
The smallest sample size needed is 49.
Step-by-step explanation:
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1-0.9}{2} = 0.05[/tex]
Now, we have to find z in the Ztable as such z has a pvalue of [tex]1-\alpha[/tex].
So it is z with a pvalue of [tex]1-0.05 = 0.95[/tex], so [tex]z = 1.645[/tex]
Now, find the margin of error M as such
[tex]M = z*\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
Find the smallest sample size n that will guarantee at least a 90% chance of the sample mean income being within $500 of the population mean income.
This is n for which [tex]M = 500, \sigma = 2119[/tex]
So
[tex]M = z*\frac{\sigma}{\sqrt{n}}[/tex]
[tex]500 = 1.645*\frac{2119}{\sqrt{n}}[/tex]
[tex]500\sqrt{n} = 1.645*2119[/tex]
[tex]\sqrt{n} = \frac{1.645*2119}{500}[/tex]
[tex](\sqrt{n})^{2} = (\frac{1.645*2119}{500})^{2}[/tex]
[tex]n = 48.6[/tex]
Rounding up
The smallest sample size needed is 49.
Answer:
[tex]n=(\frac{1.640(2119)}{500})^2 =48.31 \approx 49[/tex]
So the answer for this case would be n=49 rounded up to the nearest integer
Step-by-step explanation:
Previous concepts
A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".
The margin of error is the range of values below and above the sample statistic in a confidence interval.
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
[tex]\bar X=37500[/tex] represent the sample mean for the sample
[tex]\mu[/tex] population mean (variable of interest)
[tex]\sigma=2119[/tex] represent the sample standard deviation
n represent the sample size
Solution to the problem
The margin of error is given by this formula:
[tex] ME=z_{\alpha/2}\frac{\sigma}{\sqrt{n}}[/tex] (a)
And on this case we have that ME =500 and we are interested in order to find the value of n, if we solve n from equation (a) we got:
[tex]n=(\frac{z_{\alpha/2} \sigma}{ME})^2[/tex] (b)
The critical value for 90% of confidence interval now can be founded using the normal distribution. And in excel we can use this formla to find it:"=-NORM.INV(0.05;0;1)", and we got [tex]z_{\alpha/2}=1.640[/tex], replacing into formula (b) we got:
[tex]n=(\frac{1.640(2119)}{500})^2 =48.31 \approx 49[/tex]
So the answer for this case would be n=49 rounded up to the nearest integer
An automobile parts supplier owns a machine that produces a cylindrical engine part. This part is supposed to have an outside diameter of three inches. Parts with diameters that are too small or too large do not meet customer requirements and must be rejected. Lately, the company has experienced problems meeting customer requirements. The technical staff feels that the mean diameter produced by the machine is off target. In order to verify this, a special study will randomly sample 100 parts produced by the machine. The 100 sampled parts will be measured, and if the results obtained cast a substantial amount of doubt on the hypothesis that the mean diameter equals the target value of three inches, the company will assign a problem-solving team to intensively search for the causes of the problem.
a. The parts supplier wishes to set up a hypothesis test so that the problem-solving team will be assigned when the null hypothesis is rejected. Set up the null and alternative hypotheses for this situation.
Answer:
a) The null hypothesis is
H₀: μ₀ = 3 inches
And the alternative hypothesis is
Hₐ: μ₀ ≠ 3 inches
b) Check Explanation.
c) The $3000 is obviously the cost of a type I error.
Step-by-step explanation:
For hypothesis testing, the first thing to define is the null and alternative hypothesis.
The null hypothesis plays the devil's advocate and is always about the absence of significant difference between two proportions being compared. It usually maintains that random chance is responsible for the outcome or results of any experimental study/hypothesis testing. It usually contains the signs =, ≤ and ≥ depending on the directions of the test.
While, the alternative hypothesis takes the other side of the hypothesis; that there is indeed a significant difference between two proportions being compared. It usually confirms the the theory being tested by the experimental setup. It usually maintains that other than random chance, there are significant factors affecting the outcome or results of the experimental study/hypothesis testing. It usually contains the signs ≠, < and > depending on the directions of the test.
For this question, we want to verify that the mean diameter produced by the machine is really off-target.
Note that, that target is 3 inches.
Hence, the null hypothesis will be that that there is no difference between the mean diameter of the 100 cylinders sampled and the target of 3 inches.
And the alternative hypothesis will confirm the concerns of the technical staff that there is a significant difference between the mean diameter of the 100 cylinders sampled and the target diameter of 3 inches. That is, the mean diameter is off-target.
Mathematically,
The null hypothesis is
H₀: μ₀ = 3 inches
And the alternative hypothesis is
Hₐ: μ₀ ≠ 3 inches
b) A type I error involves rejecting the null hypothesis and accepting the alternative hypothesis when in reality, the null hypothesis is true. It involves saying there is significant evidence to show that the mean diameter of the sampled cylinders is indeed different from the targeted 3 in. (that is, the mean diameter of sampled cylinders is off-target), so they try to fix the issue when in reality, there is actually no significant difference between the mean diameter of sampled cylinders and the targeted 3 inches.
While a type II error involves failing to reject the null hypothesis when in reality it should have been rejected.
It entails not rejecting the null hypothesis and making conclusions based on the null hypothesis, when in reality, the alternative hypothesis should have been accepted together with its conclusion.
In this one the firm would conclude that they do not need to change anything as there is no significant difference between the mean diameter of the sampled cylinders and the targeted 3 inches, when in reality, there is a significant difference between the mean diameter of the sampled cylinders and the targeted 3 inches diameter.
c) The $3000 is obviously the cost of a type I error.
This is because the type I error is the one that involves tryin to fix the problem that did not even exist in reality.
Hope this Helps!!!
Answer:
Step-by-step explanation:
An Automobile Parts supplier owns a machine that produces a cylindrical engine part. The part is supposed to have an outside diameter of 3 inches in order for customers requirements to be met.
Lately, the company has been producing cylindrical engine parts with diameters that are either < 3inches or > 3inches. Technical staff feel that the mean diameter produced by the machine, from a random sample of 100 engine parts is not equal to 3 inches. The parts supplier wishes to set up a hypothesis test so that the problem-solving team can swing into action if or when the Null Hypothesis is rejected.
The null hypothesis is:
100 Cylindrical Engine Parts have a mean diameter = 3 inches
The alternative hypothesis is:
100 Cylindrical Engine Parts have a mean diameter that is NOT equal to 3 inches
[You can input the "not equal to" sign]
If the null hypothesis is rejected after statistical procedures, the supplier will proceed to employ the services of the problem-solving team!
We are interested in determining whether the variances of the sales at two music stores (A and B) are equal. A sample of 25 days of sales at store A has a sample standard deviation of 30, while a sample of 16 days of sales from store B has a sample standard deviation of 20. At 95% confidence, the null hypothesis _____.
-1/7/-5/9
Step1:
Step2:
Step3:
Answer:
9/35
Step-by-step explanation:
-1/7 ÷ -5/9
Copy dot flip
-1/7 * -9/5
Multiply the numerators
-1*-9 = 9
Multiply the denominators
7*5 = 35
9/35
Step-by-step explanation:
[tex]\frac{-\frac{1}{7} }{-\frac{5}{9} }[/tex]
Invert the fraction in the denominator and multiply it by the fraction in the numerator.
[tex](-\frac{1}{7} )(-\frac{9}{5} )\\\\\frac{9}{35}[/tex]
Factorize 12x² + 15xy
Answer:
[tex]12 {x}^{2} + 15xy \\ = 3x(4x +5 y)[/tex]
hope this helps you...
My computer is not letting me take a good quality of picture, but explanation and answer ?
Answer:
There will be 6 buses needed; the number of buses has to be a whole number.
Step-by-step explanation:
So we know that there is 232 people, and each bus holds 44 people. To find how many buses we need, you divide 232/44. Then, you get 5 with 12 extra. So you add one more bus, but that bus isn't full; there will only be 12 people inside it.
The reason why the number of buses has to be a whole number is because a bus has to be a whole bus, even though the bus isn't full. The maximum capacity of the bus is 44, but you can have 12 people inside it.
I think c is the right answer am I correct ?
Answer: yes
-5 is not greater than 4
-5
Step-by-step explanation:
Convert 100 USD to rubles. Use exchange rate, where 1 USD equals 32.5 rubles.
Answer:
3250 rubles.
Step-by-step explanation:
1 USD = 32.5 rubles so...
1 * 100 USD = 32.5 * 100 rubles.
The answer is 3250 rubles.
Answer:
3250 rubles
Step-by-step explanation:
1 USD = 32.5 rubles
100 USD = 100 × 32.5
= 3250 rubles
inDJKL side JK measures 10.6 inches side KL measures 7 inches inside JL measures 5 inches based on the information that is provided which could be a correct set of angles measured for these sides?
angle J= 23.2 angle K equals 33.5 angle owl equals 23.2
angle J equals 23.2 angle K equals 33.5 angle L equals 123.2
angle J equals 123.2 angle K equals 23.2 angle L equals 33.5
angle J equals 33.5 angle K equals 23.2 angle L equals 123.2
Answer: Angle J = 33.5°, angle K = 23.2°, angle L = 123.2°
Step-by-step explanation: i did the quiz and got it correct :D
YAHOO!!! YOU ARE CORRECT!!! LETS GIVE HIM AROUND OF APPLAUSE!!!
So thats why its "angle J equals 33.5 angle K equals 23.2 angle L equals 123.2" is the last option! (D.) U R smart, Einstein! ;)
A recent survey in the N.Y. Times Almanac indicated that 48.8% of families own stock. A broker wanted to determine if this survey could be valid. He surveyed a random sample of 250 families and found that 142 owned some type of stock. At the 0.05 significance level, can the survey be considered to be accurate?
Answer:
There is enough statistical evidence to support the claim that the survey is not accurate.
Step-by-step explanation:
We have to perform a test of hypothesis on the proportion.
The claim is that the proportion of families that own stock differs from 48.8%.
Then, the null and alternative hypothesis are:
[tex]H_0: \pi=0.488\\\\H_a:\pi\neq0.488[/tex]
The significance level is 0.05.
The sample. of size n=250, has a proportion of p=0.568.
[tex]p=X/n=142/250=0.568[/tex]
The standard error of the proportion is
[tex]\sigma_p=\sqrt{\dfrac{\pi(1-\pi)}{n}}=\sqrt{\dfrac{0.488*0.512}{250}}=\sqrt{0.00099}=0.032[/tex]
The z-statistic can now be calculated:
[tex]z=\dfrac{p-\pi-0.5/n}{\sigma_p}=\dfrac{0.568-0.488-0.5/250}{0.032}=\dfrac{0.078}{0.032}=2.4375[/tex]
The P-value for this two-tailed test is then:
[tex]P-value=2*P(z>2.4375)=0.015[/tex]
As the P-value is smaller than the significance level, the effect is significant. The null hypothesis is rejected.
There is enough evidence to support the claim that the survey is not accurate.
The suffecient eveidence to insure that the percentage of families who won stock is different from 48.8%.
Null Hypothesis:The hypothesis that there is no significant difference between specified populations, any observed difference being due to sampling or experimental error.
The null hypothesis can be stated as shown below:
[tex]H_{0} :P=48.8[/tex]%
That is, the percentage of families who own stock is [tex]48.8[/tex]%.
The alternative hypothesis can be stated as shown below:
[tex]H_{a} :p\neq 48.8[/tex]%
That is, the percentage of families who own stock is different from [tex]48.8[/tex]%
The [tex]z[/tex] test statistic is given below:
[tex]z=\frac{\hat{p-p}}{\sqrt{\frac{p\left ( 1-p \right )}{n}}}[/tex]
Here, [tex]\hat{p}[/tex] is the observed proportion then, [tex]\hat{p}[/tex] is calculated by,
[tex]\hat{p}=\frac{x}{n} \\=\frac{142}{250} \\=0.568[/tex]
Therefore,
[tex]z=\frac{\hat{p}-p}{\sqrt{\frac{p\left ( 1-p \right )}{n}}} \\=\frac{0.08}{0.0316}\\ =2.532[/tex]
Calculating the p-value be excel as attached below then we get,
The p-value is 0.01.
This p-value is called the actual level of significance.
The value of alpha is given as [tex]0.05[/tex]
Decision: The rejection of the null hypothesis [tex]H_0[/tex] because [tex]p-value < \alpha[/tex]
So, reject the null hypothesis.
Conclusion: The p-value is less than considered level of significance 5%.
Therefore the null hypothesis get rejected while the alternative hypotheisis is accepted.
Hence, there is suffecient eveidence to insure that the percentage of families who won stock is different from 48.8%.
Learn more about the topic Null Hypothesis:
https://brainly.com/question/24449949
what is factored form of x2-12x-4?
Answer:
The expression is not factorable with rational numbers...
Step-by-step explanation:
Given: ∠8 ≅ ∠16
Which lines must be parallel?
A) r and s
B) p and q
C) p and r
D) q and s
Hurry I need this one quick I don’t have a lot of time
Based on the converse of the Corresponding Angles Theorem, if ∠8 ≅ ∠16, then the lines that must be parallel are: A) r and s.
What is the converse of corresponding angles theorem?
If two lines are cut by a transversal, and the corresponding angles are congruent, then the lines are parallel, which is the converse of the Corresponding Angles Theorem.
In the image below, angles 8 and 16 are said to be congruent to each other, and both lie on lines r and s.
Therefore, based on the converse of the Corresponding Angles Theorem, lines r and s must be parallel (option A).
Which statements are true about a decagonal (10-sided) pyramid? Check all that apply.
It has one face that is a decagon.
It has two faces that are decagons.
It has 11 faces.
It has 20 edges.
It has 20 vertices.
Answer:
B. It has two faces that are decagons.
D. It has 20 edges.
E. It has 20 vertices.
Answer:b,d and e
Step-by-step explanation:
PLEASE HURRY NOW: Find the area of the rectangle below.
12 square units
24 square units
10 square units
20 square units
my question is on the picture ^
Answer:
C
Step-by-step explanation:
If the line is parallel that means 1.2 has to be the same. And passing through (5,0) means a plus five.
Decompose 0.42 into tenths and hundredths
Answer:
0.40 + 0.02
Step-by-step explanation:
4 tenths plus 2 hundredths
7 divided by 4 long division
8x-y+3x what is the answer for that
Answer:
11x-y
Step-by-step explanation:
You add 8x+3x and get 11x then you put the equation together
11x-y
HOPE THIS HELPS!!!
can someone help me with this
Christian and Tanae both leave Disneyland at the same time. Christian travels north at 65 mph. Tanae travels south at 55 mph
apart? Which of the following equations would you use to solve this word problem?
Answer:
65t+55t=540
Step-by-step explanation:
65 multiplied by four and a half equals 292.5
55 multiplied by four and a half equals 247.5
add together to get 540
If Christian travels north at 65 mph. The equations that you would use to solve this word problem is: 65t+55t=540.
Equation:The equation will be: 65t+55t=540
Where:
t=time
65=Distance to north per hour
55=Distance to south per hour
540=Miles apart
Therefore the equations that you would use to solve this word problem is: 65t+55t=540.
Learn more about equation here:https://brainly.com/question/2972832
#SPJ2
Which method would determine the volume of the prism with dimensions 2 times 2 and one-fourth times 4 shown below?
A prism has a length of 2 and one-fourth, height of 4, and width of 2 inches.
There are 8 one-quarter cubes and 16 unit cubes so (8 times one-fourth) + 16 will give the volume.
There are 8 one-quarter cubes and 8 unit cubes so (8 times one-fourth) + 8 will give the volume.
There are 8 one-quarter cubes and 16 unit cubes so (8 times 4) + 16 will give the volume.
There are 8 one-quarter cubes and 8 unit cubes so (8 times 4) + 8 will give the volume.
Answer:
THE CORRECT ANSWERS (B.)Step-by-step explanation:
Answer:
The Answer is B.
Step-by-step explanation:
I took the test on Edg 2021 and got it right the first time.
Basic Computation: Setting Hypotheses Suppose you want to test the claim that a population mean equals 30 .
(a) State the null hypothesis. ___________________________
(b) State the alternate hypothesis if you have no information regarding how the population mean might differ from 30. _________________
(c) State the alternate hypothesis if you believe (based on experience or past studies) that the population mean may be greater than 30. _______________
(d) State the alternate hypothesis if you believe (based on experience or past studies) that the population mean may not be as large as 30. ______________
Answer:
Part a
Null hypothesis: [tex]\mu =30[/tex]
Part b
Alternative hypothesis: [tex]\mu \neq 30[/tex]
Part c
Alternative hypothesis: [tex]\mu > 30[/tex]
Part d
Alternative hypothesis: [tex]\mu < 30[/tex]
Step-by-step explanation:
Previous concepts
A hypothesis is defined as "a speculation or theory based on insufficient evidence that lends itself to further testing and experimentation. With further testing, a hypothesis can usually be proven true or false".
The null hypothesis is defined as "a hypothesis that says there is no statistical significance between the two variables in the hypothesis. It is the hypothesis that the researcher is trying to disprove".
The alternative hypothesis is "just the inverse, or opposite, of the null hypothesis. It is the hypothesis that researcher is trying to prove".
Solution to the problem
For this case we want to test if the true mean is equal to 30 or no.
Part a
Null hypothesis: [tex]\mu =30[/tex]
Part b
Alternative hypothesis: [tex]\mu \neq 30[/tex]
Part c
Alternative hypothesis: [tex]\mu > 30[/tex]
Part d
Alternative hypothesis: [tex]\mu < 30[/tex]
An eight-sided die, which may or may not be a fair die, has four colors on it; you have been tossing the die for an hour and have recorded the color rolled for each toss. What is the probability you will roll an orange on your next toss of the die? Express your answer as a simplified fraction or a decimal rounded to four decimal places.
Answer:
Probability of an Orange on the next toss
= (23/60) = 0.3833
Step-by-step explanation:
Orange: 46
Brown: 23
Green: 32
Yellow: 19
Probability of an Orange on the next toss
= n(orange colours obtained in the tosses) ÷ n(number of tosses)
n(orange colours in the tosses) = 46
Total number of tosses = 46 + 23 + 32 + 19
= 120.
Probability of an Orange on the next toss
= (46/120) = (23/60) = 0.3833
Hope this Helps!!!!
The domain of the function is
The range of the function is
Answer:
Domain is where the function is defined. In other words, all valid values of x that allows us to find y.
Range is values of y for the function.
Step-by-step explanation:
Here is the example of function [tex]y = \sqrt{x}[/tex], so domin is between 0 and positive infinity. x cannot be negative.
The range is from 0 (because that's the lowest value of y) to positive infinity
Answer:
all nonzero real numbers for both of them
Step-by-step explanation:
e2021
There are 157 college students interviewed about their work schedules. 85 of them work during the day. 43 of them work nightshift. 28 students work both. How many work old dayshift?
Step-by-step explanation:
No of students work during day shift = 85
No of students work during night shift = 43
No of students working both shift = 28
So first we will divide 28 by 2 = 14
Then it means there were 14 students working in day shift and 14 students working in night shift
Total number of students work during day shift = 85 + 14 = 99
SurveyMonkey is a popular website for hosting online surveys and from time to time they will also create surveys based on a subject they are interested in answering questions about. Given the widespread adoption of dating sites and apps, they wanted to learn how people feel about them. It was found that out of 400 responses, 100 have used or are currently using online dating services. The average age of those that were using online dating services was 35 years old with a sample standard deviation of 12 years. What distribution should you use to compute a confidence interval for the average age of people using online dating services
Answer:
So we use the t-distribution to compute a confidence interval for the average age of people using online dating services
Step-by-step explanation:
Confidence interval for a mean.
We have to decide between the t-distribution and the z-distribution.
T-distribution: We use the sample standard deviation.
Z-distribution: We use the population standard deviation.
In this problem:
The average age of those that were using online dating services was 35 years old with a sample standard deviation of 12 years.
So we use the t-distribution to compute a confidence interval for the average age of people using online dating services
You are a personnel director and are interested in predicting the Number of Shares of Company Stock (Y) using the Number of Years Employed with the Company (X). You randomly selected 8 employees and found that the average number of shares is 525 and the average number of years employed is 22.5. If the slope (b1) is 20.0, what is the least squares estimate of the intercept (b0)
Answer:
intercept=b0=75
Step-by-step explanation:
The least squares estimate of the intercept b0 can be computed as
b0=ybar-b1*xbar.
ybar=average number of shares of company stock=525.
xbar= average number of years employed=22.5.
slope=b1=20.
Thus,
intercept=b0=ybar-b1*xbar
intercept=b0=525-20*22.5
intercept=b0=525-450
intercept=b0=75.
Thus, the estimate of intercept b0=75.
A staff member at UF's Wellness Center is interested in seeing if a new stress reduction program will lower employees high blood pressure levels. Twenty people are selected and have their blood pressure measured. Each person then participates in the stress reduction program. One month after the stress reduction program, the blood pressure levels of the employees were measured again. Did the program reduce the average blood pressure level? The 95% confidence interval was (5.6, 10.2). What can we expect will be the p-value for a two sided test using this data? Group of answer choices The p-value should be smaller than 0.95 The p-value should be larger than 0.95 The p-value should be smaller than 0.05. The p-value should be higher than 0.05.
Answer:
The p-value should be smaller than 0.05.
Step-by-step explanation:
We know that the 95% confidence interval for the difference of means is (5.6, 10.2). As the lower bound is larger than 0, we are 95% confident that the reduction program had had a effect in the blood pressure level.
Then, as the program had a significant effect in the blood pressure level, we know that the null hypothesis (that states that the blood pressure levels would no change significantly) is then rejected.
If the significance level is 0.05, according to the confidence of the interval, to reject the null hypothesis, the p-value had to be lower than the significance level. In conclusion, the p-value should be lower than 0.05.
What is/are the factor(s) in the "Sub-U-Like" study?
A. 30-second, 60-second and 90-second commercials
B. The number of students
C. Craving for Sub-U-Like
D. The length of the television program
E. Length and frequency of the commercial.
F. One, three, or five commercials during the 50-minute television program
Answer:
E. Length and frequency of the commercial.
Remaining Details of the Question:
A study investigated the effect of the length and the repetition of TV advertisements on students' desire to eat at a Sub-U-Like sandwich franchise. Sixty students watched a 50- minute television program that showed at least one commercial for Sub-U-Like during advertisement breaks. Some students saw a 30-second commerical, some saw a 60-second commercial, others a 90-second commerical. The same commerical was shown one, three, or five times during the program. After the viewing, each student was asked to rate their craving for a Sub-U-Like sandwich from the set ("Don't want to eat", "Neutral", "Want to eat"}
Explanation:
During the course of an experimental study, it is important to identify the variables of interest. These variables are referred to as the factors. Factors are controlled independent variables in an experimental study that can be manipulated by the experimenter.
In this case, it was indicated that the study investigated the effect of the length and the repetition of TV advertisements on students' desire to eat at a Sub-U-Like sandwich franchise. Therefore, the factors in the "Sub-U-Like" study are length and frequency of the commercial.
Final answer:
The factors in the "Sub-U-Like" study include the length and frequency of the commercial, the number of students, and the number of commercials during the TV program. Factors in the "Sub-U-Like" study, while not explicitly defined in the examples provided, can generally include variables such as length and frequency of commercials and the number of commercials shown, all of which can influence viewers' behaviors and perceptions in psychological or marketing research.
Explanation:
Factors in the "Sub-U-Like" study:
Factor A: Length and frequency of the commercial
Factor B: The number of students
Factor F: One, three, or five commercials during the 50-minute television program