In how many ways can $8$ people be divided into
$4$ groups of $2$ people
First pair, second pair. Third pair and the fourth pair
How do you go about doing this question?
In how many ways can $8$ people be divided into
$4$ groups of $2$ people
First pair, second pair. Third pair and the fourth pair
How do you go about doing this question?
4 groups of 2 people:
_ _ _ _ _ _ _ _ ( 8.7/2! * 6.5/2! * 4.3/2! * 2.1/2! )/4!
First pair, second pair. Third pair and the fourth pair:
1º pair -> 8*7/2! = 28 2º pair -> 6*5/2! = 15 ... -> ...