Problem
COM-B1-M01-P011 Team with a Condition
#11
★★☆☆☆ Level 2 of 5
From \(4\) boys and \(3\) girls, a team of \(3\) is chosen. How many teams contain at least one girl?
Subtract all-boy teams from all teams.
There are \(35\) teams of \(3\) from \(7\) people. All-boy teams: \(4\). Therefore the answer is \(35-4=31\).
The number \(35\) can be explained by choosing triples without emphasizing a formula.