MathDB
A Dance Party

Source:

June 13, 2009

Problem Statement

At a dance party a group of boys and girls exchange dances as follows: one boy dances with 5 5 girls, a second boy dances with 6 6 girls, and so on, the last boy dancing with all the girls. If b b represents the number of boys and g g the number of girls, then: (A)\ b \equal{} g\qquad (B)\ b \equal{} \frac{g}{5}\qquad (C)\ b \equal{} g \minus{} 4\qquad (D)\ b \equal{} g \minus{} 5\qquad \\ (E)\ \text{It is impossible to determine a relation between }{b}\text{ and }{g}\text{ without knowing }{b \plus{} g.}