Answer:
Step-by-step explanation:
Given the following :
Average amount spent (U) = $130 per trip
Sample size (n) = 25
Sample mean (m) = $135.25
Population standard deviation (sd) = $10.50
Assume a standard distribution.
A.) Null hypothesis ; Alternative hypothesis
Hnull : U ≤ 130 ; Ha : U > 130
B.) value of test statistic :
Z = (m - U) / standard error
Standard Error = sd / sqrt(n)
Standard Error( S.E)= 10.50 / sqrt(25)
S.E = 10.50 / 5 = 2.1
Hence,
Z = (135.25 - 130) / 2.1
Z = 5.25 / 2.1
Z = 2.5
C. Calculate the p-value.
Using the p value calculator by entering the z-score above, the p value obtained is 0.0124
P value = 0.01
D. Calculate the critical value