Xuan bought some buttons. She gave
16 of the buttons to her cousin and sold
56 of the remaining buttons. After that, she bought another 217 buttons and had the same number of buttons that she bought at first. How many buttons did Xuan buy at first?
| Her cousin |
Remaining buttons |
Bought buttons |
Total |
1x6 =
6 u |
5x6 =
30 u |
|
6x6 =
36 u |
| |
Sold |
Left |
|
|
| |
5x5 |
1x5 |
|
|
| 6 u |
25 u |
5 u |
217 |
|
The remaining number of buttons before Xuan bought another 217 buttons is repeated. Make the remaining number of buttons the same. LCM of 5 and 6 is 30.
Total number of buttons at first = 36 u
Number of buttons that Xuan had left and bought after that = 5 u + 217
36 u = 5 u + 217
36 u - 5 u = 217
31 u = 217
1 u = 217 ÷ 31 = 7
Total number of buttons at first
= 36 u
= 36 x 7
= 252
Answer(s): 252
