PSLE Billy was given a fixed amount of allowance each month. In September, he saved $150 and spent the rest. In October, he saved 40% more and his spending decreased by 20%. How much was Billy's allowance for each month?
|
Savings (%) |
Spending (u) |
Before |
100% $$(n80 |
100 u |
Change |
+ 40% |
- 20 u |
After |
140% |
80 u |
100% of savings = 150
1% of savings = 150 ÷ 100 = 1.5
40% of savings = 40% x 150 = 60
40% of savings = 20 u of spending
20 u of spending = 60
1 u of spending = 60 ÷ 20 = 3
100 u of spending = 100 x 3 = 300
Billy's allowance for each month
= 100% of savings + 100 u of spending
= 150 + 300
= $450
Answer(s): $450