Aki spent 3/8 of his pocket money on food, 2/5 of the rest on transport and returned the remaining amount to his mother. What fraction of the money did he give back to his mother?
3/8 = 15/40
2/5 = 16/40
sum = 31/40
1 - sum = 9/40
To find the fraction of money that Aki gave back to his mother, we need to calculate the remaining amount after spending on food and transport.
Step-by-step solution:
1. Let's assume Aki started with 1 whole unit of pocket money.
2. Aki spent 3/8 of his pocket money on food. So the amount remaining after spending on food is (1 - 3/8) = 5/8.
3. Now, Aki spent 2/5 of the remaining amount on transport. Multiplying this by the remaining amount (5/8), we get ((5/8) * (2/5)) = 10/40 = 1/4.
4. The fraction remaining after spending on transport is (5/8 - 1/4) = (5/8 - 2/8) = 3/8.
5. Therefore, Aki gave back 3/8 of the money to his mother.