Can you please explain how to calculate this on Exel?

To find P-Value :-

Here, alternative hypothesis is of "=" type, so this is two-tailed test.

Its p-value will be given by

P-Value = 2 * Pr( T < -|t| )

= 2 * Pr( T < -|0.2972| )

P-Value = 2 * Pr( T < - 0.2972 )

where T is t-distributed with df = n₁ + n₂ -2 = 40+75-2 = 113 degree of freedom

Now required probability Pr( T < - 0.2972 ) can be computed from from t-table or more accurately from any software like R,Excel

In R, we use function "pt(t,df)" to find Pr(T

Using R

> 2*pt(-0.2972,df=113)   # 2 * Pr( T < - 0.2972 ) [1] 0.7668595

Thus, we get

P-Value = 2 * Pr( T < - 0.2972 ) = 0.7668

P-Value = 0.7668