Problema Solution

Ashley has 4 CDs that she is going to give away. She lets her best friend choose 3 of the 4 CDs. How many different groups of 3 CDs are possible?

Answer provided by our tutors

Since the order of the CD's is not important, here we are dealing with combinations.

The number of 2-combinations from a given set of 4 elements: 

C(4, 3)

Using the formula fo calculating calculations:

We have:

C(4, 3) = 4!/(4 - 3)!3!

C(4, 3) = 4

There are 4 different groups of 3 CDs possible.