Statistics

1. Statistics Chapter 7 Review

2. A car maker claims that its new sub-compact car gets better than 49 miles per gallon on the highway. Determine whether the hypothesis test is left-tailed, right-tailed, or two-tailed. • Left-tailed • Right-tailed • Two-tailed

3. The mean age of bus drivers in Chicago is 48.9 years. If a hypothesis test is performed, how should you interpret a decision that fails to reject the null hypothesis? • There is not enough evidence to reject the claim. • There is sufficient evidence to reject the claim. • There is no enough evidence to support the claim. • There is sufficient evidence to support the claim.

4. Find the critical value for a two-tailed test with a α = 0.01 and n = 30. • ± 1.645 • ± 1.96 • ± 2.33 • ± 2.575

5. You wish to test the claim that 47 at a significance level of α= 0.01 and are given sample statistics n = 40, mean = 48.8, and s = 4.3. Compute the value of the standardized test statistic. • 3.51 • 1.96 • 2.12 • 2.65

6. Suppose you are using α= 0.01 to test the claim that μ≤40 using a P-value. You are given the sample statistics n = 40, mean = 41.8, and s = 4.3. Find the P-value. • 0.0211 • 0.1030 • 0.0040 • 0.9960

7. Given Ha: μ > 85 and P = 0.006. Do you reject or fail to reject Ho at the 0.01 level of significance? • Reject Ho • Fail to reject Ho • Not sufficient information to decide.

8. Find the standardized test statistic t for a sample with n = 15, mean = 6.4, and s = 0.8, and α= 0.05 if Ho: μ≤ 6.1. • 1.631 • 1.312 • 1.728 • 1.452

9. Determine whether the normal sampling distribution can be used. The claim is p ≠ 0.300 and the sample size is n = 20. • Do not use the normal distribution. • Use the normal distribution.

10. Find the critical χ2-value to test the claim σ2 ≥ 1.8 if n = 15 and α = 0.05. • 4.660 • 6.571 • 5.629 • 4.075

11. Compute the standardized test statistic, χ2, to test the claim σ2 > 15.2 if n = 18, s2 = 21.6, and α = 0.01. • 24.158 • 28.175 • 43.156 • 33.233