Dana bought some erasers. She gave
17 of the erasers to her brother and sold
25 of the remaining erasers. After that, she bought another 204 erasers and had the same number of erasers that she bought at first. How many erasers did Dana buy at first?
| Her brother |
Remaining erasers |
Bought erasers |
Total |
1x5 =
5 u |
6x5 =
30 u |
|
7x5 =
35 u |
| |
Sold |
Left |
|
|
| |
2x6 |
3x6 |
|
|
| 5 u |
12 u |
18 u |
204 |
|
The remaining number of erasers before Dana bought another 204 erasers is repeated. Make the remaining number of erasers the same. LCM of 6 and 5 is 30.
Total number of erasers at first = 35 u
Number of erasers that Dana had left and bought after that = 18 u + 204
35 u = 18 u + 204
35 u - 18 u = 204
17 u = 204
1 u = 204 ÷ 17 = 12
Total number of erasers at first
= 35 u
= 35 x 12
= 420
Answer(s): 420
