Question

A boy spends 3/4 of his pocket money and then 4/5 of the remainder is given to his sister if he had rupees 40 left what did he have first?

Answer 1

boy spend 3/4

remaining = 1 - 3/4 = 1/4

gave 4/5 to sister

remaining 1 - 4/5 = 1/5

let he had x rupees

1/4 of 1/5 of x = 40

1/4 * 1/5 * x = 40

x = 800