Question

Adrian earns 16000 per month. He spends 1/4 of his income on food, 3/10 of the remainder on his house rent and 5/21 of the remainder on the education of children. How much money is still left with him?

Answer 1

1/4 of $160 is $40. 3/10 of $120 is $36.
5/21 of 84 is $20.16. This leaves him with $63.84.