PSLE Riordan was given a fixed amount of allowance each month. In September, he spent $240 and saved the rest. In October, he spent 10% less and his savings increased by 30%. How much was Riordan's allowance for each month?
|
Spending (%) |
Savings (u) |
Before
|
100% $240 |
100 u
|
Change |
- 10% |
+ 30 u |
After |
90% |
130 u |
100% of spending = 240
1% of spending = 240 ÷ 100 = 2.4
10% of spending = 10% x 240 = 24
10% of spending = 30 u of savings
30 u of savings = 24
1 u of savings = 24 ÷ 30 = 0.8
100 u of savings = 100 x 0.8 = 80
Riordan's allowance for each month
= 100% of spending + 100 u of savings
= 240 + 80
= $320
Answer(s): $320