Question

The Business College Computing Center wants to determine the proportion of business students who have laptop computers. If the proportion is more than from​ 30%, then the lab will modify a proposed enlargement of its facilities. Suppose a hypothesis test is conducted and the test statistic is 2.8. Find the ​p-value for a​ one-sided test of hypothesis.

A. .0026

B..0013

C. .4938

D. .0052

Suppose​ students' ages follow a skewed right distribution with a mean of 25 years old and a standard deviation of 4 years. If we randomly sample 250 ​students, which of the following statements about the sampling distribution of the sample mean age is​ incorrect?

A.The standard deviation of the sampling distribution is equal to 4 years.

B.The mean of the sampling distribution is approximately 25 years old.

C.The shape of the sampling distribution is approximately normal.

D.All of the above statements are correct.

A local​ eat-in pizza restaurant wants to investigate the possibility of starting to deliver pizzas. The owner of the store has determined that home delivery will be successful only if the average time spent on a delivery does not exceed 25 minutes. The owner has randomly selected 15 customers and delivered pizzas to their homes in order to test whether the mean delivery time actually exceeds 25 minutes. Suppose the​ p-value for the test was found to be 0.0295 State the correct conclusion.

A.At alphaαequals=​0.05, we fail to reject Upper H 0H0.

B.At alphaαequals=​0.025, we fail to reject Upper H 0H0.

C.At alphaαequals=​0.02, we reject Upper H 0H0.

D.At alphaαequals=​0.03, we fail to reject Upper H 0H0.

Answer 1

1. Here test statistics is 2.8

And claim is that p>0.30

So P value is P(z>2.8)=0.0026

Hence answer here is A. 0.0026

2. Here sample size is sufficient large so sample mean is normally distributed with sd=sigma/sqrt(n)=4/sqrt(250)

So incorrect answer here is

A.The standard deviation of the sampling distribution is equal to 4 years.

3. As we know for P value <alpha we reject the null hypothesis. So for alpha=0.025 we fail to reject the H0

B.At alphaαequals=​0.025, we fail to reject Upper H 0.