Yen and Gillian had $168. Gillian had $36 more than Yen. Yen spent 4 times as much as Gillian and was left with
25 as much as Gillian. How much did Gillian spend less than Yen?
| |
Make p the same
(1) x 5 = (3) |
Yen
(1) |
Gillian
(2) |
Make p the same
(2) x 2 = (4) |
Total
|
Comparing Yen
and Gillian 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 Yen had at first
= (168 - 36) ÷ 2
= 132 ÷ 2
= $66
Amount that Gillian 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 Gillian spent less than Yen
= 4 u - 1 u
= 3 u
= 3 x 7
= $21
Answer(s): $21
