A.

A sample of 24 account balances of a credit company showed an average balance of $1,173 and a standard deviation of $100. You want to determine if the mean of all account balances issignificantlygreater than $1,150. Use a 0.05 level of significance. Assume the population ofaccount balances is normally distributed.

Compute the test statistic.

B.

A sample of 25 account balances of a credit company showed an average balance of $1,170 and a standard deviation of $125. You want to determine if the mean of all account balances issignificantlygreater than $1,150. Assume the population ofaccount balances is normally distributed.

Compute the p-value for this test.

C.

A sample of28account balances of a credit company was taken to testwhetherthe mean of all account balances issignificantlygreater than$1,150.Using the samplestandard deviation,the test statistic (t) was calculated to be$2.29.We use a 0.05 level of significance. Assume the population ofaccount balances is normally distributed and the population standard deviation is unknown to us.

We conclude that the mean of all account balancesis significantly greater than$1,150.(Enter1if the conclusion is correct.Enter0if the conclusion is wrong.)

D.

The U.S. Bureau of Labor Statistics reports that 11.5% of U.S. workers belong to unions. Suppose a sample of 347U.S. workers is collected in 2014 to determine whether union efforts to organize have increased union membership.The sample results show that 53of the workers belonged to unions.

Compute the test statistics.