PSLE Jack was given a fixed amount of allowance each month. In July, he saved $390 and spent the rest. In August, he saved 10% less and his spending increased by 30%. How much was Jack's allowance for each month?
|
Savings (%) |
Spending (u) |
Before
|
100% $390 |
100 u
|
Change |
- 10% |
+ 30 u |
After |
90% |
130 u |
100% of savings = 390
1% of savings = 390 ÷ 100 = 3.9
10% of savings = 10% x 390 = 39
10% of savings = 30 u of spending
30 u of spending = 39
1 u of spending = 39 ÷ 30 = 1.3
100 u of spending = 100 x 1.3 = 130
Jack's allowance for each month
= 100% of savings + 100 u of spending
= 390 + 130
= $520
Answer(s): $520