Question

A credit reporting agency claims that the mean credit card debt in a town is greater than $3500. A random sample of the credit card debt of 20 residents in that town has a mean credit card debt of $3619 and a standard deviation of $391. At α=0.10, can the credit agency’s claim be supported?

Yes, since p-value of 0.19 is greater than 0.10, fail to reject the null. Claim is null, so is supported

No, since p-value of 0.09 is greater than 0.10, reject the null. Claim is null, so is not supported

No, since p-value of 0.09 is greater than 0.10, fail to reject the null. Claim is alternative, so is not supported

Yes, since p-value of 0.09 is less than 0.55, reject the null. Claim is alternative, so is supported

Flag this Question

Question 192 pts

A car company claims that its cars achieve an average gas mileage of at least 26 miles per gallon. A random sample of eight cars form this company have an average gas mileage of 25.6 miles per gallon and a standard deviation of 1 mile per gallon. At α=0.06, can the company’s claim be supported?

Yes, since the test statistic of -1.13 is not in the rejection region defined by the critical value of -1.55, the null is rejected. The claim is the null, so is supported

No, since the test statistic of -1.13 is in the rejection region defined by the critical value of -1.77, the null is rejected. The claim is the null, so is not supported

Yes, since the test statistic of -1.13 is not in the rejection region defined by the critical value of -1.77, the null is not rejected. The claim is the null, so is supported

No, since the test statistic of -1.13 is close to the critical value of -1.24, the null is not rejected. The claim is the null, so is supported

Answer 1

Answer - 1: The statistical software output for this problem is:

One sample T summary hypothesis test:
μ : Mean of population
H₀ : μ = 3500
H_A : μ > 3500

Hypothesis test results:

Mean	Sample Mean	Std. Err.	DF	T-Stat	P-value
μ	3619	87.430258	19	1.3610849	0.0947

Hence,

Yes, since p-value of 0.09 is less than 0.10, reject the null. Claim is alternative, so is supported.

Option D is correct.

Answer - 2: The statistical software output for this problem is:

One sample T summary hypothesis test:
μ : Mean of population
H₀ : μ = 26
H_A : μ < 26

Hypothesis test results:

Mean	Sample Mean	Std. Err.	DF	T-Stat	P-value
μ	25.6	0.35355339	7	-1.1313708	0.1476

Hence,

Option D is correct.