Exam 7: Hypothesis Testing With One Sample

In one area, monthly incomes of college graduates have a standard deviation of $650. It is believed that the standard deviation of monthly incomes of non-college graduates is higher. A sample of 71 non-college graduates are randomly selected and found to have a standard deviation of $950. Test the claim that non-college graduates have a higher standard deviation. Use $\alpha$ = 0.05.

The mean score for all NBA games during a particular season was less than 104 points per game. If a hypothesis test is performed, how should you interpret a decision that fails to reject the null hypothesis?

Test the claim about the population mean μ at the level of significance α. Assume the population is normally distributed. $\text { Claim } \mu < 7.4 ; \alpha = 0.10 \text {. Sample statistics: } \bar { x } = 7 , s = 2.0 , \mathrm { n } = 20$

The mean age of bus drivers in Chicago is greater than 54.1 years. If a hypothesis test is performed, how should you interpret a decision that rejects the null hypothesis?

The dean of a major university claims that the mean time for students to earn a Masterʹs degree is at most 3.3 years. Write the null and alternative hypotheses.

Test the claim about the population mean $\mu$ at the level of significance α $\alpha$ Assume the population is normally distributed. $\text { Claim } \mu > 33 ; \alpha = 0.005 \text {. Sample statistics: } \bar { x } = 34 , s = 3 , n = 25$

The dean of a major university claims that the mean time for students to earn a Masterʹs degree is at most 3.5 years. If a hypothesis test is performed, how should you interpret a decision that rejects the null hypothesis?

Find the P-value for the hypothesis test with the standardized test statistic z. Decide whether to reject H₀ for the level of significance α. Right-tailed test Z = 0.52 $\alpha$ = 0.05

Test the claim that $\sigma \leq 10.74 \text { if } \mathrm { n } = 20 , \mathrm {~s} = 14.94 \text {, and } \alpha = 0.01 \text {. }$ Assume that the population is normally distributed.

Test the claim that $\sigma = 6.21 \text { if } \mathrm { n } = 12 , \mathrm {~s} = 5.7 \text {, and } \alpha = 0.05 \text {. }$ .05. Assume that the population is normally distributed.

The P-value for a hypothesis test is P = 0.006. Do you reject or fail to reject $\mathrm { H } _ { 0 }$ when the level of significance is $\alpha$ α = 0.01?

Test the claim that $\sigma \geq 6.7 \text { if } \mathrm { n } = 15 , \mathrm {~s} = 6.1 \text {, and } \alpha = 0.05 \text {. }$ Assume that the population is normally distributed.

Find the critical value and rejection region for the type of z-test with level of significance α $\alpha$ Two-tailed test, α $\alpha$ = 0.06

A local group claims that the police issue more than 60 speeding tickets a day in their area. To prove their point, they randomly select two weeks. Their research yields the number of tickets issued for each day. The data are listed below. At α $\alpha$ = 0.01, test the groupʹs claim. 70 48 41 68 69 55 70 57 60 83 32 60 72 58

Find the standardized test statistic t for a sample with $\mathrm { n } = 15 , \overline { \mathrm { x } } = 7.2 , \mathrm {~s} = 0.8 \text {, and } \alpha = 0.05 \text { if } \mathrm { H } _ { 0 } : \mu \leq 6.9 \text {. }$ Round your answer to three decimal places.

A fast food outlet claims that the mean waiting time in line is less than 3.5 minutes. A random sample of 60 customers has a mean of 3.6 minutes with a population standard deviation of 0.6 minute. If α $\alpha$ = 0.05, test the fast food outletʹs claim using critical values and rejection regions.

Find the critical value and rejection region for the type of z-test with level of significance α $\alpha .$ Left-tailed test, α $\alpha = 0.05$

Test the claim that $\sigma < 16.59 \text { if } \mathrm { n } = 28 , \mathrm {~s} = 13.09 \text { and } \alpha = 0.10 \text {. }$ Assume that the population is normally distributed.

Test the claim about the population mean $\mu$ at the level of significance α. Assume the population is normally distributed. Claim: $\mu > 28 ; \alpha = 0.05 ; \sigma = 1.2$ Sample statistics: $\bar { x } = 28.3 , n = 50$