Dana bought some stamps. She gave
17 of the stamps to her sister and sold
34 of the remaining stamps. After that, she bought another 121 stamps and had the same number of stamps that she bought at first. How many stamps did Dana buy at first?
| Her sister |
Remaining stamps |
Bought stamps |
Total |
1x2 =
2 u |
6x2 =
12 u |
|
7x2 =
14 u |
| |
Sold |
Left |
|
|
| |
3x3 |
1x3 |
|
|
| 2 u |
9 u |
3 u |
121 |
|
The remaining number of stamps before Dana bought another 121 stamps is repeated. Make the remaining number of stamps the same. LCM of 6 and 4 is 12.
Total number of stamps at first = 14 u
Number of stamps that Dana had left and bought after that = 3 u + 121
14 u = 3 u + 121
14 u - 3 u = 121
11 u = 121
1 u = 121 ÷ 11 = 11
Total number of stamps at first
= 14 u
= 14 x 11
= 154
Answer(s): 154
