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Question 3: Quickshave produces disposable razorblades. They claim that the mean number of shaves before a blade has to be thrown away is 13. A researcher wishing to test the claim asks 31} men to supply data on how many shaves they get om one Quickshave blade. The researcher found the sample mean was 12.8 and the sample standard deviation was 1.6. Perform a t-test with a 5% level of significance to test the manufacturer's claim. t = .685 ;p value = 11.499