Age frequencies with two unknowns

Core stretch

The ages 13, 14, 15, 16 occur with frequencies 3, \(x\), \(y\), 4, for 20 students.

1. Given that 15 is the unique mode, write an inequality involving \(x\) and \(y\).[1]
2. If 40% of the students are aged 15, find \(x\) and \(y\).[2]