Adam and Bryan have a total of $48.
Adam spends
14 of his money and
Bryan spends
16 of his money.
They spend $10 altogether.
- How much does Adam have at first?
- How much does Bryan have in the end?
|
Adam |
Bryan |
Before |
4 u |
6 p |
Change |
- 1 u |
- 1 p |
After |
3 u |
5 p |
(a)
Amount that Adam has at first = 4 u
Amount that Bryan has at first = 6 p
Total amount that they have = 4 u + 6 p = 48 --- (1)
Total amount that they spend = 1 u + 1 p = 10 --- (2)
(2)
x 6 6 u + 6 p = 60 --- (3)
(3) - (1)
(6 u + 6 p) - (4 u + 6 p) = 60 - 48
6 u + 6 p - 4 u - 6 p = 60 - 48
6 u - 4 u + 6 p - 6 p = 12
6 u - 4 u = 12
2 u = 12
1 u = 12 ÷ 2 = 6
Substitute 1 u = 6 into (1).
4 u + 6 p = 48
4 x 6 + 6 p = 48
24 + 6 p = 48
6 p = 48 - 24 = 24
1 p = 24 ÷ 6 = 4
Amount that Adam has at first
= 4 u
= 4 x 6
= $24
(b)
Amount that Bryan has in the end
= 6 p - 1 p
= 5 p
= 5 x 4
= $20
Answer(s): (a) $24; (b) $20