Min bought some stamps. She gave
14 of the stamps to her sister and sold
25 of the remaining stamps. After that, she bought another 110 stamps and had the same number of stamps that she bought at first. How many stamps did Min buy at first?
| Her sister |
Remaining stamps |
Bought stamps |
Total |
1x5 =
5 u |
3x5 =
15 u |
|
4x5 =
20 u |
| |
Sold |
Left |
|
|
| |
2x3 |
3x3 |
|
|
| 5 u |
6 u |
9 u |
110 |
|
The remaining number of stamps before Min bought another 110 stamps is repeated. Make the remaining number of stamps the same. LCM of 3 and 5 is 15.
Total number of stamps at first = 20 u
Number of stamps that Min had left and bought after that = 9 u + 110
20 u = 9 u + 110
20 u - 9 u = 110
11 u = 110
1 u = 110 ÷ 11 = 10
Total number of stamps at first
= 20 u
= 20 x 10
= 200
Answer(s): 200
