PSLE Ken was given a fixed amount of allowance each month. In January, he saved $40 and spent the rest. In February, he saved 20% more and his spending decreased by 10%. How much was Ken's allowance for each month?
|
Savings (%) |
Spending (u) |
Before |
100% $$(n80 |
100 u |
Change |
+ 20% |
- 10 u |
After |
120% |
90 u |
100% of savings = 40
1% of savings = 40 ÷ 100 = 0.4
20% of savings = 20% x 40 = 8
20% of savings = 10 u of spending
10 u of spending = 8
1 u of spending = 8 ÷ 10 = 0.8
100 u of spending = 100 x 0.8 = 80
Ken's allowance for each month
= 100% of savings + 100 u of spending
= 40 + 80
= $120
Answer(s): $120