Ken, Mark and Ben had 126 buttons. After Ken used 32 buttons and Mark used
17 of her buttons, Ken had twice as many buttons left as Mark. Ben bought another 35 buttons, he had four times the number of buttons Mark had left. How many buttons did Ben have at first?
| |
Ken |
Mark |
Ben |
Total |
| Before |
12 u + 32 |
7 u |
24 u - 35 |
126 |
| Change |
- 32 |
- 1 u |
+ 35 |
|
| After |
12 u |
6 u |
24 u |
|
Comparing Ken
and Mark in the end |
2 |
1 |
|
|
Comparing Ben
and Mark in the end |
|
1 |
4 |
|
Number of buttons that Ken had in the end
= 2 x 6 u
= 12 u
Number of buttons that Ben had in the end
= 4 x 6 u
= 24 u
Total number of buttons at first
= 12 u + 32 + 7 u + 24 u - 35
= 43 u - 3
43 u - 3 = 126
43 u = 126 + 3
43 u = 129
1 u = 129 ÷ 43 = 3
Number of buttons that Ben had at first
= 24 u - 35
= 24 x 3 - 35
= 72 - 35
= 37
Answer(s): 37
