The answer is: " 21 ".
__________________________________________________________
Twenty-one (21) individuals participated in the study.
__________________________________________________________
Explanation:
__________________________________________________________
In this case:
"degrees of freedom" {df) = n - 1 = 20 ;
in which:
"n" refers to the "sample size" ;
that is ; the "total number of individuals who participated in the study" .
" n - 1 = 20 " ; Solve for "n" ;
Add "1" to each side of the equation:
n - 1 + 1 = 20 + 1 ;
n = 21 ;
__________________________________________________________
The answer is: " 21 ".
__________________________________________________________
