Answer to Question #125013 in Statistics and Probability for Irene

Question

A significance test for means gave a t =-1.97 with degrees of freedom 10.
Can you reject the null hypothesis when you have a non-directional test at the 5% significance level?

Answer 1

Probability for t = -1.97 for df = 10 is between 0.025 and 

0.05( using t table ).

So for two-sided test, the p-value is between 0.05 and 0.1. Therefore we fail to reject H0 at the significance level alpha = 0.05.

P value is also calculated is by a software ti84 or p value calculator .You see 

the exact P-value (0.07714)