Adam and Bryan have a total of $260.
Adam spends
14 of his money and
Bryan spends
18 of his money.
They spend $34 altogether.
- How much does Adam have at first?
- How much does Bryan have in the end?
|
Adam |
Bryan |
Before |
4 u |
8 p |
Change |
- 1 u |
- 1 p |
After |
3 u |
7 p |
(a)
Amount that Adam has at first = 4 u
Amount that Bryan has at first = 8 p
Total amount that they have = 4 u + 8 p = 260 --- (1)
Total amount that they spend = 1 u + 1 p = 34 --- (2)
(2)
x 8 8 u + 8 p = 272 --- (3)
(3) - (1)
(8 u + 8 p) - (4 u + 8 p) = 272 - 260
8 u + 8 p - 4 u - 8 p = 272 - 260
8 u - 4 u + 8 p - 8 p = 12
8 u - 4 u = 12
4 u = 12
1 u = 12 ÷ 4 = 3
Substitute 1 u = 3 into (1).
4 u + 8 p = 260
4 x 3 + 8 p = 260
12 + 8 p = 260
8 p = 260 - 12 = 248
1 p = 248 ÷ 8 = 31
Amount that Adam has at first
= 4 u
= 4 x 3
= $12
(b)
Amount that Bryan has in the end
= 8 p - 1 p
= 7 p
= 7 x 31
= $217
Answer(s): (a) $12; (b) $217