Question

Davon is picking out some movies to rent, and he has narrowed down his selections to 4 children's movies, 3 documentaries, 6 comedies, and 5 mysteries. How many different combinations of 9 movies can he rent if he wants all 6 comedies?

Answer 1

220

Explanation:

There are 6 comedies and 12 non-comedies. He wants all 6 of the comedies, and 3 of the non-comedies.

The number of ways he can choose 6 comedies from 6 is ₆C₆ = 1.

The number of ways he can choose 3 non-comedies from 12 is ₁₂C₃ = 220.

So the total number of combinations is 1 × 220 = 220.