## Disco Ratios

#### Problem

The ratio of boys to girls at a school disco is 9:10.

An extra 17 boys arrive and the ratio changes to 8:7.

How many girls are there at the disco?

Problem ID: 131 (Nov 2003) Difficulty: 2 Star

The ratio of boys to girls at a school disco is 9:10.

An extra 17 boys arrive and the ratio changes to 8:7.

How many girls are there at the disco?

Problem ID: 131 (Nov 2003) Difficulty: 2 Star