Betty bought some stickers. She gave
14 of the stickers to her cousin and sold
25 of the remaining stickers. After that, she bought another 77 stickers and had the same number of stickers that she bought at first. How many stickers did Betty buy at first?
| Her cousin |
Remaining stickers |
Bought stickers |
Total |
1x5 =
5 u |
3x5 =
15 u |
|
4x5 =
20 u |
| |
Sold |
Left |
|
|
| |
2x3 |
3x3 |
|
|
| 5 u |
6 u |
9 u |
77 |
|
The remaining number of stickers before Betty bought another 77 stickers is repeated. Make the remaining number of stickers the same. LCM of 3 and 5 is 15.
Total number of stickers at first = 20 u
Number of stickers that Betty had left and bought after that = 9 u + 77
20 u = 9 u + 77
20 u - 9 u = 77
11 u = 77
1 u = 77 ÷ 11 = 7
Total number of stickers at first
= 20 u
= 20 x 7
= 140
Answer(s): 140
