Need help with combination problem...?

Question

Can someone explain to me the steps of solving this problem?

Given a group of 6 people, find the number of ways to select from that group a committee that contains at least 4 people.

The "at least" part is what messes me up. It wouldn't be 6C4, would it?

Answer 1

At least 4 means 4 or more, so it would be 6C4 + 6C5 + 6C6, which equals

6C2 + 6C1 + 6C0 = (6)(5)/2 + 6 + 1 = 15 + 6 + 1 = 22