PSLE Perry was given a fixed amount of allowance each month. In August, he spent $110 and saved the rest. In September, he spent 20% more and his savings decreased by 10%. How much was Perry's allowance for each month?
|
Spending (%) |
Savings (u) |
Before |
100% $$(n80 |
100 u |
Change |
+ 20% |
- 10 u |
After |
120% |
90 u |
100% of spending = 110
1% of spending = 110 ÷ 100 = 1.1
20% of spending = 20% x 110 = 22
20% of spending = 10 u of savings
10 u of savings = 22
1 u of savings = 22 ÷ 10 = 2.2
100 u of savings = 100 x 2.2 = 220
Perry's allowance for each month
= 100% of spending + 100 u of savings
= 110 + 220
= $330
Answer(s): $330