Olivia and Kimberly had $158. Kimberly had $42 more than Olivia. Olivia spent 4 times as much as Kimberly and was left with
25 as much as Kimberly. How much did Olivia spend more than Kimberly?
| |
Make p the same
(1)x5 = (3) |
Olivia
(1) |
Kimberly
(2) |
Make p the same
(2)x2 = (4) |
Total
|
Comparing Olivia
and Kimberly at first |
|
|
$42 more |
|
$158 |
| Before |
$290 |
$58 |
$100 |
$200 |
|
| Change |
- 20 u |
- 4 u |
- 1 u |
- 2 u |
|
| After |
10 p |
2 p |
5 p |
10 p |
|
Amount that Olivia had at first
= (158 - 42) ÷ 2
= 116 ÷ 2
= $58
Amount that Kimberly had at first
= 58 + 42
= $100
58 - 4 u = 2 p --- (1)
100 - 1 u = 5 p --- (2)
Make p the same.
(1)
x 5
290 - 20 u =
10 p --- (3)
(2)
x 2
200 - 2 u =
10 p --- (4)
(4) = (3)
200 - 2 u = 290 - 20 u
20 u - 2 u = 290 - 200
18 u = 90
1 u = 90 ÷ 18 = 5
Amount that Olivia spent more than Kimberly
= 4 u - 1 u
= 3 u
= 3 x 5
= $15
Answer(s): $15
