Adam spends $400 of his income and saves the rest.
When he increases his savings by 20%, his spending decreases by 40%
- How much is Adam's spending at first?
- How much is Adam's spending in the end?
- How much is Adam's income?
|
Savings |
Spending |
Before |
100% |
100 u |
Change |
+ 20% |
- 40 u |
After |
120% |
60 u |
(a)
20% of Adam's savings = 40% of Adam's spending
100% of Adam's savings = $400
1% of Adam's savings = 400 ÷ 100 = $4
20% of Adam's savings = 20 x 4 = $80
40 u of Adam's spending = $80
1 u of Adam's spending = 80 ÷ 40 = $2
100 u of Adam's spending = 100 x 2 = $200
Amount of Adam's spending at first
= 100 u
= $200
(b)
Amount of spending in the end
= 60 u
= 60 x 2
= $120
(c)
Adam's income
= 100% + 100 u
= 400 + 200
= $600
Answer(s): (a) $200; (b) $120; (c) $600