Adam and Bryan have a total of $173.
Adam spends
12 of his money and
Bryan spends
15 of his money.
They spend $43 altogether.
- How much does Adam have at first?
- How much does Bryan have in the end?
|
Adam |
Bryan |
Before |
2 u |
5 p |
Change |
- 1 u |
- 1 p |
After |
1 u |
4 p |
(a)
Amount that Adam has at first = 2 u
Amount that Bryan has at first = 5 p
Total amount that they have = 2 u + 5 p = 173 --- (1)
Total amount that they spend = 1 u + 1 p = 43 --- (2)
(2)
x 5 5 u + 5 p = 215 --- (3)
(3) - (1)
(5 u + 5 p) - (2 u + 5 p) = 215 - 173
5 u + 5 p - 2 u - 5 p = 215 - 173
5 u - 2 u + 5 p - 5 p = 42
5 u - 2 u = 42
3 u = 42
1 u = 42 ÷ 3 = 14
Substitute 1 u = 14 into (1).
2 u + 5 p = 173
2 x 14 + 5 p = 173
28 + 5 p = 173
5 p = 173 - 28 = 145
1 p = 145 ÷ 5 = 29
Amount that Adam has at first
= 2 u
= 2 x 14
= $28
(b)
Amount that Bryan has in the end
= 5 p - 1 p
= 4 p
= 4 x 29
= $116
Answer(s): (a) $28; (b) $116