Bryan and Adam have a total of $251.
Bryan spends
12 of his money and
Adam spends
17 of his money.
They spend $48 altogether.
- How much does Bryan have at first?
- How much does Adam have in the end?
|
Bryan |
Adam |
Before |
2 u |
7 p |
Change |
- 1 u |
- 1 p |
After |
1 u |
6 p |
(a)
Amount that Bryan has at first = 2 u
Amount that Adam has at first = 7 p
Total amount that they have = 2 u + 7 p = 251 --- (1)
Total amount that they spend = 1 u + 1 p = 48 --- (2)
(2)
x 7 7 u + 7 p = 336 --- (3)
(3) - (1)
(7 u + 7 p) - (2 u + 7 p) = 336 - 251
7 u + 7 p - 2 u - 7 p = 336 - 251
7 u - 2 u + 7 p - 7 p = 85
7 u - 2 u = 85
5 u = 85
1 u = 85 ÷ 5 = 17
Substitute 1 u = 17 into (1).
2 u + 7 p = 251
2 x 17 + 7 p = 251
34 + 7 p = 251
7 p = 251 - 34 = 217
1 p = 217 ÷ 7 = 31
Amount that Bryan has at first
= 2 u
= 2 x 17
= $34
(b)
Amount that Adam has in the end
= 7 p - 1 p
= 6 p
= 6 x 31
= $186
Answer(s): (a) $34; (b) $186