PSLE Billy was given a fixed amount of allowance each month. In November, he spent $250 and saved the rest. In December, he spent 20% more and his savings decreased by 10%. How much was Billy's allowance for each month?
|
Spending (%) |
Savings (u) |
Before |
100% $$(n80 |
100 u |
Change |
+ 20% |
- 10 u |
After |
120% |
90 u |
100% of spending = 250
1% of spending = 250 ÷ 100 = 2.5
20% of spending = 20% x 250 = 50
20% of spending = 10 u of savings
10 u of savings = 50
1 u of savings = 50 ÷ 10 = 5
100 u of savings = 100 x 5 = 500
Billy's allowance for each month
= 100% of spending + 100 u of savings
= 250 + 500
= $750
Answer(s): $750