The median of the following distribution is 52.5.find the value of x a

This question was asked in Ex 14.1, 2

The median of the following distribution is 52.5.find the value of x and y if the total frequency is 100.
Class.0-10 10-20 20-30 30-40 40-50 50-60 60-70 70-80 80-90 90-100
Frequency.2 5 x 12 17 20 y 9 7 4