PSLE Mark was given a fixed amount of allowance each month. In February, he spent $210 and saved the rest. In March, he spent 10% more and his savings decreased by 20%. How much was Mark's allowance for each month?
|
Spending (%) |
Savings (u) |
Before |
100% $$(n80 |
100 u |
Change |
+ 10% |
- 20 u |
After |
110% |
80 u |
100% of spending = 210
1% of spending = 210 ÷ 100 = 2.1
10% of spending = 10% x 210 = 21
10% of spending = 20 u of savings
20 u of savings = 21
1 u of savings = 21 ÷ 20 = 1.05
100 u of savings = 100 x 1.05 = 105
Mark's allowance for each month
= 100% of spending + 100 u of savings
= 210 + 105
= $315
Answer(s): $315