Adam spends $500 of his income and saves the rest.
When he increases his savings by 20%, his spending decreases by 25%
- 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% |
- 25 u |
After |
120% |
75 u |
(a)
20% of Adam's savings = 25% of Adam's spending
100% of Adam's savings = $500
1% of Adam's savings = 500 ÷ 100 = $5
20% of Adam's savings = 20 x 5 = $100
25 u of Adam's spending = $100
1 u of Adam's spending = 100 ÷ 25 = $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
= 75 u
= 75 x 4
= $300
(c)
Adam's income
= 100% + 100 u
= 500 + 400
= $900
Answer(s): (a) $400; (b) $300; (c) $900