Question

An aspirin manufacturer claims their tablets have a mean weight of 5 grains. We take a sample of 100 tablets (assume this n is large enough for CLT to kick in) and find a mean weight of 4.87 grains and sample standard deviation of .35 grains. At a 0.05% level of significance is there enough evidence to show that the mean weight of aspirin tablets is less than 5 grains? Also compute p-value.

A. Do not reject null, p-value is 0.035

B. Reject null, p-value is 0.0001

C. Reject null, p-value is 0.035

D. Reject null, p-value is 0.0002

Answer 1

Answer

using TI 84 calculator

press stat then tests then T-test

enter the data

press enter, we get

p value = 1.686E-4

so, p value is 0.0002 (rounded to 4 decimals)

p value is less than 0.05 significance level, so we can reject the null hypothesis

option D