Use the information provided below to answer questions

A national troop leader wishes to estimate the mean ( ) daily cookie sales by the Girl Scouts. A random sample of 25 (= n) girls has a daily average sales value of $15 (= x-bar) and a standard deviation (= s) of $2. The population standard deviation is $2.50 (=). Using this information, what would be the value of the point estimate?

Referencing the information, the correct sampling distribution to use when developing the confidence interval to estimate the mean ( ) daily cookie sales is:

a. the normal (z) distribution.

b. a discrete probability distribution.

c. a frequency distribution.

d. the t-distribution.

Referencing the information provided, what would be the interval estimate for the mean cookie sales if the troop leader wants to be 98% confident in her estimate?

Formula Choices:

Meanz ( n)

Meanz ( s n)

Meant ( sn )

a. $13.00 - $17.00

b. $12.50 - $17.50

c. $14.17 - $15.83

d. $13.83 - $16.17

Referencing the information provided, if the national troop leader increased her sample size from 25 girls to 49 girls, and all other variables remained unchanged, then:

a. the width of the confidence interval would become wider.

b. the probability of error would increase.

c. the width of the confidence interval would become narrower.

d. the correct sampling distribution would change from the t-distribution to the z-distribution.

Referencing the information provided, if the national troop leader decided to decrease the confidence level from 98% to 95%, and the sample size remained at 25 girls, then:

a. the Standard Error of the Means will increase.

b. the width of the confidence interval would become wider.

c. the width of the confidence interval would become narrower.

d. the probability that Mu ( ) will equal x-bar increases.