Ivan and Bobby went shopping with a total amount of $448. They had $384 left after shopping. Ivan's remaining money was 5 times the amount he paid for. Bobby's remaining money was 7 times the amount he had spent.
- How much did Bobby spend?
- How much did Bobby bring along for shopping?
| |
Ivan |
Bobby |
Total |
| Before |
6 u |
8 p |
448 |
| Change |
- 1 u |
- 1 p |
- 64 |
| After |
5 u |
7 p |
384 |
(a)
Amount that Ivan and Bobby spent
= 448 - 384
= $64
Amount that Ivan and Bobby spent
= 1 u + 1 p
1 u + 1 p = 64
1 u = 64 - 1 p --- (1)
Amount that Ivan and Bobby had left
= 5 u + 7 p
5 u + 7 p = 384
5 u = 384 - 7 p --- (2)
Make u the same.
(1)
x 5 5 u = 320 - 5 p --- (3)
(3) = (2)
320 - 5 p = 384 - 7 p
7 p - 5 p = 384 - 320
2 p = 64
1 p = 64 ÷ 2 = 32
Amount that Bobby spent = $32
(b)
Amount that Bobby brought along
= 8 p
= 8 x 32
= $256
Answer(s): (a) $32; (b) $256
