Respuesta :

wolf1728

We want to select 3 pairs of people from a group of 6.

We use the formula:

n! / (r! * (n -r)!)

where n = 6 and r = 2

combinations = 6! / (2! * 4!) =

combinations = 6 * 5 / 2

combinations = 15


Source:

1728.com/combinat.htm