Ahmad and Ethan had the same number of cards at first. After Ahmad had bought another 31 cards and Ethan had lost 9 of his cards, Ahmad had thrice as many cards as Ethan. How many cards did each of them have at first?
| |
Ethan |
Ahmad |
| Before |
1 u + 9 |
3 u - 31 |
| Change |
- 9 |
+ 31 |
| After |
1 u |
3 u |
Ahmad and Ethan had the same number of cards at first.
3 u - 31 = 1 u + 9
3 u - 1 u = 9 + 31
2 u = 40
1 u = 40 ÷ 2 = 20
Number of cards that each of them had at first
= 1 u + 9
= 20 + 9
= 29
Answer(s): 29
