Cathy and Nicole had $154. Nicole had $30 more than Cathy. Cathy spent 4 times as much as Nicole and was left with
25 as much as Nicole. How much did Nicole spend less than Cathy?
| |
Make p the same
(1) x 5 = (3) |
Cathy
(1) |
Nicole
(2) |
Make p the same
(2) x 2 = (4) |
Total
|
Comparing Cathy
and Nicole at first |
|
|
$30 more |
|
$154 |
| Before |
$310 |
$62 |
$92 |
$184 |
|
| Change |
- 20 u |
- 4 u |
- 1 u |
- 2 u |
|
| After |
10 p |
2 p |
5 p |
10 p |
|
Amount that Cathy had at first
= (154 - 30) ÷ 2
= 124 ÷ 2
= $62
Amount that Nicole had at first
= 62 + 30
= $92
62 - 4 u = 2 p --- (1)
92 - 1 u = 5 p --- (2)
Make p the same.
(1)
x 5
310 - 20 u =
10 p --- (3)
(2)
x 2
184 - 2 u =
10 p --- (4)
(4) = (3)
184 - 2 u = 310 - 20 u
20 u - 2 u = 310 - 184
18 u = 126
1 u = 126 ÷ 18 = 7
Amount that Nicole spent less than Cathy
= 4 u - 1 u
= 3 u
= 3 x 7
= $21
Answer(s): $21
