Now using n1 80179 degrees of freedom we can find the pvalue

Now using n-1 (80-1=79) degrees of freedom we can find the p-value using a t chart or a graphing calculator. This will come out to be about 0.1869

Can someone explain how they got this answer when the t-table doesn\'t have row 79?

Solution

They got this value using technology. (We cannot do this using a table).

When you use a graphing calculator like ti-84, then you can use the tcdf function:

tcdf(lower t value, upper t value, degrees of freedom)