2013 HMMT Guts #4: Spencer and his Burritos
Source:
March 26, 2013
HMMTcomplementary counting
Problem Statement
Spencer is making burritos, each of which consists of one wrap and one filling. He has enough filling for up to four beef burritos and three chicken burritos. However, he only has five wraps for the burritos; in how many orders can he make exactly five burritos?