From a given data,

sample size, n = 101

sample mean,x = 7

sample standard deviation, s = 2

Degree of freedom = n - 1

= 101 - 1

= 100

Confidence level = 95%

Probability = 1 - 0.95

= 0.05

Two tailed critical value for 100 degree of freedom and 95% confidence is,

t_c = 1.984 (Use Excel formula: =T.INV.2T(0.05,100)

95% CI =xtcns

=71.9841002

=70.397

Suppose the mean and the standard deviation were based on a sample size n = 25 postal workers rather than 101. What do we know about the value of the P-value? Answers

A) It would be smaller.

B) It would be larger.

C) It would be unchanged, because the difference between x and the hypothesized value 7.5 is unchanged.

D) It would be unchanged, because the variability measured by the standard deviation stays the same.