PSLE Riordan was given a fixed amount of allowance each month. In September, he spent $450 and saved the rest. In October, he spent 40% more and his savings decreased by 10%. How much was Riordan's allowance for each month?
|
Spending (%) |
Savings (u) |
Before |
100% $$(n80 |
100 u |
Change |
+ 40% |
- 10 u |
After |
140% |
90 u |
100% of spending = 450
1% of spending = 450 ÷ 100 = 4.5
40% of spending = 40% x 450 = 180
40% of spending = 10 u of savings
10 u of savings = 180
1 u of savings = 180 ÷ 10 = 18
100 u of savings = 100 x 18 = 1800
Riordan's allowance for each month
= 100% of spending + 100 u of savings
= 450 + 1800
= $2250
Answer(s): $2250