Question 1

The state of CT claims that the average time on death row is 15 years. A random survey of 75 death row inmates revealed that the average length of time on death row is 17.7 years with a standard deviation of 6.2 years. Conduct a hypothesis to test the state of CT's claim. What type of test should be run?

• z-test of a proportion
• t-test of a mean The alternative hypothesis indicates a
• left-tailed test
• two-tailed test
• right-tailed test Calculate the p-value. What is the decision?
• We reject the claim that the average time on death row is 15 years
• We fail to reject the claim that the average time on death row is 15 years

Question 2

Test the claim that the mean GPA of night students is larger than 2.8 at the 1% significance level. The population standard deviation for this group is known to be 0.12. The null and alternative hypotheses for this test are:

0:2.8 :>2.8 0:2.8 :<2.8 The test is:left-tailed or right-tailed Based on a sample of 38 people, the sample mean GPA was 2.81. Hint: Before you find the p-value below, calculate the test statistic to two decimal places. The p-value is: (to 4 decimals) The significance level as a decimal is: Based on this we

• fail to reject the null hypothesis, 0
• reject the null hypothesis, 0

Question 3

Fayech University claims that the mean GPA of night students is approximately normally distributed with mean 3.5 with a population standard deviation of 0.05.

We wish to test the claim that the mean GPA of night students is smaller than 3.5 at the 0.01 significance level.

Based on a sample of 75 people, we find the sample mean GPA was 3.48. The null and alternative hypothesis would be:

0:=3.5 1:>3.5 0:=3.5 1:<3.5 0:=3.5 1:>3.5 0:=3.5 1:3.5 0:=3.5 1:3.5 0:=3.5 1:<3.5 The test is:

left-tailed right-tailed two-tailed We should use a:

• z-test for the proportion
• z-test for the mean
• t-test for the mean
• The test statistic is?: (to 2 decimals) The p-value is?: (to 2 decimals) Based on this we:
• Reject the null hypothesis or
• Fail to reject the null hypothesis

Question 4

Test the claim that the mean GPA of night students is significantly different than 2.3 at the 0.02 significance level. The null and alternative hypothesis would be:0:=2.3 1:>2.3 0:=2.3 1:<2.3 0:=0.575 1:<0.575 0:=2.3 1:2.3 0:=0.575 1:>0.575 0:=0.575 1:0.575 The test is? :left-tailed two-tailed right-tailed Based on a sample of 25 people, the sample mean GPA was 2.33 with a standard deviation of 0.03 The test statistic is: (to 2 decimals) The positive critical value is: (to 2 decimals) Based on this we:

• Fail to reject the null hypothesis
• Reject the null hypothesis

Question 5

Someone claims the average electronics department does not earn $3000 each day. 0: ? p X X p N n s ? = < > dollars : ? p s X n X N p ? = > < dollars After performing a hypothesis test, P-value > We should Select an answer fail to reject reject

• 0
• Conclusion: There is Select an answer significant insufficient evidence to Select an answer support reject the claim that the average electronic department does not earn $3000 each day.

Question 6

Test the claim that the mean GPA of night students is smaller than 2.3 at the 10% significance level. The population standard deviation for this group is known to be 0.2. The null and alternative hypotheses for this test are:

0:2.3 :>2.3 0:2.3 :<2.3 The test is :left-tailed or right-tailed Based on a sample of 35 people, the sample mean GPA was 2.26. Hint: Before you find the p-value below, calculate the test statistic to two decimal places. The p-value is: (to 4 decimals) The significance level as a decimal is: Based on this we

• fail to reject the null hypothesis, 0
• reject the null hypothesis, 0

Question 7

As part of your work for an environmental group, you want to see if the mean amount of waste generated per adult in your community is less than the national average of 5 pounds per day. You take a simple random sample of 25 adults in your community and find that they average 4.1 pounds with a standard deviation of 1.3 pounds. Suppose you know the amount of waste generated per day follows a normal distribution. Test at 0.10 significance. Round answers to 4 decimal places.

1. H₀: Select an answer s p p s x ? > = <
2. H₁: Select an answer s x p s p ? > = <
3. Test Statistic:
4. P-value:
5. Select the Decision Rule: Select an answer Reject the null hypothesis Do not reject the null hypothesis. Accept the null claim Reject the alternative hypothesis.
6. There Select an answer is not is enough evidence to conclude

Question 8

An oceanographer claims that the mean dive depth of a North Atlantic right whale is 108 meters. You suspect that this claim is not true. In order to refute the oceanographer's claim, you obtain a random sample of 40 dive depths with a mean of 120 meters and a standard deviation of 46.4 meters. State the null and alternative hypotheses of this test. Round answers to 4 decimal places. Use a significance level of = 0.10.

1. H₀: Select an answer s x p p s ? = > < meters
2. H₁: Select an answer s p s p x ? = < > meters
3. The test statistic is
4. The p-value for this hypothesis test is .
5. The correct decision is:
6. Is the result considered significant?
7. We conclude that:
   • We can dispute the oceanographer's claim that the mean dive depth of a North Atlantic right whale is 108 meters at the 0.10 level of significance.
   • We cannot dispute the oceanographer's claim that the mean dive depth of a North Atlantic right whale is 108 meters at the 0.10 level of significance.

• Yes. The result is significant because the p-value is .
• Yes. The result is significant because the p-value is >.
• No. The result is not significant because the p-value is >.
• No. The result is not significant because the p-value is .
• Reject the claim.
• Reject the null hypothesis.
• Do not reject the null hypothesis.
• Reject the alternative hypothesis.

Question 9

Fayech University claims that the mean GPA of night students is approximately normally distributed with mean 3.2 with a population standard deviation of 0.06.

We wish to test the claim that the mean GPA of night students is smaller than 3.2 at the 0.025 significance level.

Based on a sample of 20 people, we find the sample mean GPA was 3.18. The null and alternative hypothesis would be:

0:=3.2 1:<3.2 0:=3.2 1:>3.2 0:=3.2 1:<3.2 0:=3.2 1:3.2 0:=3.2 1:>3.2 0:=3.2 1:3.2 The test is:

right-tailed left-tailed two-tailed We should use a:

• z-test for the mean
• z-test for the proportion
• t-test for the mean The test statistic is: (to 2 decimals) The p-value is: (to 2 decimals) Based on this we:
• Fail to reject the null hypothesis
• Reject the null hypothesis

Question 10

Test the claim that the proportion of men who own cats is larger than 10% at the .10 significance level. The null and alternative hypothesis would be: 0:=0.1 1:0.1 0:=0.1 1:>0.1 0:=0.1 1:0.1 0:=0.1 1:>0.1 0:=0.1 1:<0.1 0:=0.1 1:<0.1 Incorrect The test is: left-tailed two-tailed right-tailed Based on a sample of 100 people, 17% owned cats The test statistic is: (to 2 decimals) The critical value is: (to 2 decimals) Based on this we:

• Fail to reject the null hypothesis
• Reject the null hypothesis

Question 11

Test the claim that the proportion of people who own cats is smaller than 80% at the 0.025 significance level. The null and alternative hypothesis would be:

0:=0.8 1:0.8 0:0.8 1:<0.8 0:=0.8 1:0.8 0:0.8 1:>0.8 0:0.8 1:<0.8 0:0.8 1:>0.8 The test is:

two-tailed right-tailed left-tailed Based on a sample of 500 people, 71% owned cats The test statistic is: (to 2 decimals) The p-value is: (to 2 decimals) Based on this we:

• Fail to reject the null hypothesis
• Reject the null hypothesis

Question 12

Test the claim that the proportion of people who own cats is smaller than 80% at the 0.025 significance level. The null and alternative hypothesis would be:

0:=0.8 1:0.8 0:0.8 1:<0.8 0:=0.8 1:0.8 0:0.8 1:>0.8 0:0.8 1:<0.8 0:0.8 1:>0.8 The test is:

two-tailed right-tailed left-tailed Based on a sample of 500 people, 71% owned cats The test statistic is: (to 2 decimals) The p-value is: (to 2 decimals) Based on this we:

• Fail to reject the null hypothesis
• Reject the null hypothesis

Question 13

Test the claim that the mean GPA of night students is significantly different than 2.4 at the 0.02 significance level. The null and alternative hypothesis would be:0:=0.6 1:>0.6 0:=0.6 1:<0.6 0:=2.4 1:>2.4 0:=2.4 1:2.4 0:=0.6 1:0.6 0:=2.4 1:<2.4 Correct The test is? :two-tailed left-tailed right-tailed Based on a sample of 25 people, the sample mean GPA was 2.43 with a standard deviation of 0.02 The test statistic is: (to 2 decimals) The positive critical value is: (to 2 decimals) Based on this we:

• Reject the null hypothesis
• Fail to reject the null hypothesis

Question 14

Test the claim that the mean GPA of night students is larger than 2.6 at the 0.05 significance level. The null and alternative hypothesis would be:

0:=0.65 1:0.65 0:=2.6 1:2.6 0:2.6 1:<2.6 0:0.65 1:<0.65 0:0.65 1:>0.65 0:2.6 1:>2.6 The test is:

right-tailed left-tailed two-tailed Based on a sample of 25 people, the sample mean GPA was 2.62 with a standard deviation of 0.07 The test statistic is: (to 2 decimals) The p-value is: (to 2 decimals) Based on this we:

• Fail to reject the null hypothesis
• Reject the null hypothesis

Question 15

• Find an example of a Hypothesis Test online (or make up an example of your own.)
• State the Type I and Type II Errors for the Hypothesis Test
• Write at least two sentences on which error (Type I or Type II) is more serious in your opinion.

Please, answer the questions sequentially. Thank you.