Coach Grunt is preparing the 5-person starting lineup for his basketball team, the Grunters.  There are 12 players on the team.  Two of them, Ace and Zeppo, are league All-Stars, so they'll definitely be in the starting lineup.  How many different starting lineups are possible?  (The order of the players in a basketball lineup doesn't matter.)
I need to choose 3 more players out of the remaining 10, since Ace and Zeppo are already in. This is a combination problem, since the order doesn't matter. The formula for combinations is nCr = n!/(r!(n-r)!), where n is the total number of choices and r is the number of selections. In this case, n = 10 and r = 3, so nCr = 10!/(3!(10-3)!) = 120. Therefore, there are 120 different starting lineups possible for Coach Grunt. 