A vessel contains 100 litres of petrol. A shopkeeper removes some percent of petrol and replaced with diesel and this process done for two times. The ratio of petrol and diesel in the resultant mixture is 16 : 9. Find the amount of diesel he adds to the mixture.
1
36 litres
2
30 litres
3
25 litres
4
35 litres
5
18 litres