Bryan and Adam have a total of $206.
Bryan spends
15 of his money and
Adam spends
17 of his money.
They spend $32 altogether.
- How much does Bryan have at first?
- How much does Adam have in the end?
|
Bryan |
Adam |
Before |
5 u |
7 p |
Change |
- 1 u |
- 1 p |
After |
4 u |
6 p |
(a)
Amount that Bryan has at first = 5 u
Amount that Adam has at first = 7 p
Total amount that they have = 5 u + 7 p = 206 --- (1)
Total amount that they spend = 1 u + 1 p = 32 --- (2)
(2)
x 7 7 u + 7 p = 224 --- (3)
(3) - (1)
(7 u + 7 p) - (5 u + 7 p) = 224 - 206
7 u + 7 p - 5 u - 7 p = 224 - 206
7 u - 5 u + 7 p - 7 p = 18
7 u - 5 u = 18
2 u = 18
1 u = 18 ÷ 2 = 9
Substitute 1 u = 9 into (1).
5 u + 7 p = 206
5 x 9 + 7 p = 206
45 + 7 p = 206
7 p = 206 - 45 = 161
1 p = 161 ÷ 7 = 23
Amount that Bryan has at first
= 5 u
= 5 x 9
= $45
(b)
Amount that Adam has in the end
= 7 p - 1 p
= 6 p
= 6 x 23
= $138
Answer(s): (a) $45; (b) $138