PSLE Ivan was given a fixed amount of allowance each month. In September, he saved $480 and spent the rest. In October, he saved 10% more and his spending decreased by 20%. How much was Ivan's allowance for each month?
|
Savings (%) |
Spending (u) |
Before |
100% $$(n80 |
100 u |
Change |
+ 10% |
- 20 u |
After |
110% |
80 u |
100% of savings = 480
1% of savings = 480 ÷ 100 = 4.8
10% of savings = 10% x 480 = 48
10% of savings = 20 u of spending
20 u of spending = 48
1 u of spending = 48 ÷ 20 = 2.4
100 u of spending = 100 x 2.4 = 240
Ivan's allowance for each month
= 100% of savings + 100 u of spending
= 480 + 240
= $720
Answer(s): $720