Tammy and Diana had the same number of stamps. After Tammy had given away 78 stamps, Diana had 3 times as many stamps as Tammy. How many stamps did each of them have at first?
| |
Tammy |
Diana |
| Before |
1 u + 78 |
3 u |
| Change |
- 78 |
|
| After |
1 u |
3 u |
Number of stamps that Diana had remains unchanged.
Number of stamps that Tammy and Diana had at first is equal.
3 u = 1 u + 78
3 u - 1 u = 78
2 u = 78
1 u = 78 ÷ 2= 39
Number of stamps that each of them had at first
= 1 u + 78
= 39 + 78
= 117
Answer(s): 117
