Question

The claim is that for the population of adult​ males, the mean platelet count is μ>217. The sample size is n=50 and the test statistic is t=1.421. I know the answer is 0.081 but I don't understand how to get that answer. Can someone please explain how to find a p-value using the test statistic either manually or with a calculator?

Answer 1

Step-by-step explanation:

First, find the degrees of freedom:

df = n − 1

df = 49

To find the p-value manually, use a t-score table.  Find the row corresponding to 49 degrees of freedom.  Then find the α column that corresponds to a t-score of 1.421.  You'll find it's between α = 0.10 (t = 1.299) and α = 0.05 (t = 1.677).  Interpolating, we get an approximate p-value of 0.084.  For a more accurate answer, you'll need to use a calculator.