Question

A club has 10 members.

If the club is sending 3 members to a convention, how many different groups of 3 members are possible?

Answer 1

Okay so you have 10 members. So you would go 10 divided by 3 that is equal to 9 with one left over. 

Answer 2

that is the combination of 10 over 3, which is calculated as the quotient of factorials:
n!/k!(n-k)!
where n = 10 and k = 3:
= 10!/3!(10 - 3)!
= 10!/3!*7!
= (10*9*8)/(3*2*1)
= 720/6
= 120
therefore there a re 120 possible different groups