Michael and Billy had the same number of cards at first. After Michael had bought another 28 cards and Billy had lost 10 of his cards, Michael had thrice as many cards as Billy. How many cards did each of them have at first?
| |
Billy |
Michael |
| Before |
1 u + 10 |
3 u - 28 |
| Change |
- 10 |
+ 28 |
| After |
1 u |
3 u |
Michael and Billy had the same number of cards at first.
3 u - 28 = 1 u + 10
3 u - 1 u = 10 + 28
2 u = 38
1 u = 38 ÷ 2 = 19
Number of cards that each of them had at first
= 1 u + 10
= 19 + 10
= 29
Answer(s): 29
