Warren and Carl went shopping with a total amount of $480. They had $400 left after shopping. Warren's remaining money was 4 times the amount he paid for. Carl's remaining money was 6 times the amount he had spent.
- How much did Carl spend?
- How much did Carl bring along for shopping?
| |
Warren |
Carl |
Total |
| Before |
5 u |
7 p |
480 |
| Change |
- 1 u |
- 1 p |
- 80 |
| After |
4 u |
6 p |
400 |
(a)
Amount that Warren and Carl spent
= 480 - 400
= $80
Amount that Warren and Carl spent
= 1 u + 1 p
1 u + 1 p = 80
1 u = 80 - 1 p --- (1)
Amount that Warren and Carl had left
= 4 u + 6 p
4 u + 6 p = 400
4 u = 400 - 6 p --- (2)
Make u the same.
(1)
x 4 4 u = 320 - 4 p --- (3)
(3) = (2)
320 - 4 p = 400 - 6 p
6 p - 4 p = 400 - 320
2 p = 80
1 p = 80 ÷ 2 = 40
Amount that Carl spent = $40
(b)
Amount that Carl brought along
= 7 p
= 7 x 40
= $280
Answer(s): (a) $40; (b) $280
