# Statistics: T-test: Testing hypotheses – #94

Question: A copy machine is advertised as doing 25,000 copies before requiring service. A consumer group wants to check this claim. If 12 customers had a mean of 24,800 copies with a standard deviation of 180, test at the .01 level.

State the hypotheses and identify the claim, find the critical value(s), compute the test value, and make the decision, summarize the results.