The tensile strength of paper using 5% hardwood and 10% hardwood are to be compared. A random sample of 41 sheets made from 5% hardwood had an average tensile strength of 1.52 lbs. with a standard deviation of 0.33 lbs. A random sample of 61 sheets made from 10% hardwood had an average tensile strength of 1.88 lbs. with a standard deviation of 0.42 lbs.
Can we conclude the average tensile strength is the same for the two types of paper? Use 5% significance and p-values.
Part 1) Conduct the test using the assumption that the sample standard deviations are the same as the population standard deviations.
Part 2) Conduct the test using the assumption that the population standard deviations are unknown but equal (you also must assume a normal population here).
Part 3) Conduct the test with only the assumption that we have simple random samples from normal populations.
May you please explain which stat test you used on your calculator and why. Thank you very much for your help!
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