Esther and Yen had $168. Yen had $36 more than Esther. Esther spent 4 times as much as Yen and was left with
25 as much as Yen. How much did Esther spend?
| |
Make p the same
(1)x5 = (3) |
Esther
(1) |
Yen
(2) |
Make p the same
(2)x2 = (4) |
Total
|
Comparing Esther
and Yen at first |
|
|
$36 more |
|
$168 |
| Before |
$330 |
$66 |
$102 |
$204 |
|
| Change |
- 20 u |
- 4 u |
- 1 u |
- 2 u |
|
| After |
10 p |
2 p |
5 p |
10 p |
|
Amount that Esther had at first
= (168 - 36) ÷ 2
= 132 ÷ 2
= $66
Amount that Yen had at first
= 66 + 36
= $102
66 - 4 u = 2 p --- (1)
102 - 1 u = 5 p --- (2)
Make p the same.
(1)
x 5
330 - 20 u =
10 p --- (3)
(2)
x 2
204 - 2 u =
10 p --- (4)
(4) = (3)
204 - 2 u = 330 - 20 u
20 u - 2 u = 330 - 204
18 u = 126
1 u = 126 ÷ 18 = 7
Amount that Esther spent
= 4 u
= 4 x 7
= $28
Answer(s): $28
