Bryan and Adam have a total of $236.
Bryan spends
14 of his money and
Adam spends
18 of his money.
They spend $42 altogether.
- How much does Bryan have at first?
- How much does Adam have in the end?
|
Bryan |
Adam |
Before |
4 u |
8 p |
Change |
- 1 u |
- 1 p |
After |
3 u |
7 p |
(a)
Amount that Bryan has at first = 4 u
Amount that Adam has at first = 8 p
Total amount that they have = 4 u + 8 p = 236 --- (1)
Total amount that they spend = 1 u + 1 p = 42 --- (2)
(2)
x 8 8 u + 8 p = 336 --- (3)
(3) - (1)
(8 u + 8 p) - (4 u + 8 p) = 336 - 236
8 u + 8 p - 4 u - 8 p = 336 - 236
8 u - 4 u + 8 p - 8 p = 100
8 u - 4 u = 100
4 u = 100
1 u = 100 ÷ 4 = 25
Substitute 1 u = 25 into (1).
4 u + 8 p = 236
4 x 25 + 8 p = 236
100 + 8 p = 236
8 p = 236 - 100 = 136
1 p = 136 ÷ 8 = 17
Amount that Bryan has at first
= 4 u
= 4 x 25
= $100
(b)
Amount that Adam has in the end
= 8 p - 1 p
= 7 p
= 7 x 17
= $119
Answer(s): (a) $100; (b) $119