Adam spends $200 of his income and saves the rest.
When he increases his savings by 10%, his spending decreases by 5%
- 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 |
+ 10% |
- 5 u |
After |
110% |
95 u |
(a)
10% of Adam's savings = 5% of Adam's spending
100% of Adam's savings = $200
1% of Adam's savings = 200 ÷ 100 = $2
10% of Adam's savings = 10 x 2 = $20
5 u of Adam's spending = $20
1 u of Adam's spending = 20 ÷ 5 = $4
100 u of Adam's spending = 100 x 4 = $400
Amount of Adam's spending at first
= 100 u
= $400
(b)
Amount of spending in the end
= 95 u
= 95 x 4
= $380
(c)
Adam's income
= 100% + 100 u
= 200 + 400
= $600
Answer(s): (a) $400; (b) $380; (c) $600