Betty bought some buttons. She gave
14 of the buttons to her brother and sold
34 of the remaining buttons. After that, she bought another 65 buttons and had the same number of buttons that she bought at first. How many buttons did Betty buy at first?
| Her brother |
Remaining buttons |
Bought buttons |
Total |
1x4 =
4 u |
3x4 =
12 u |
|
4x4 =
16 u |
| |
Sold |
Left |
|
|
| |
3x3 |
1x3 |
|
|
| 4 u |
9 u |
3 u |
65 |
|
The remaining number of buttons before Betty bought another 65 buttons is repeated. Make the remaining number of buttons the same. LCM of 3 and 4 is 12.
Total number of buttons at first = 16 u
Number of buttons that Betty had left and bought after that = 3 u + 65
16 u = 3 u + 65
16 u - 3 u = 65
13 u = 65
1 u = 65 ÷ 13 = 5
Total number of buttons at first
= 16 u
= 16 x 5
= 80
Answer(s): 80
