Xavier, David and Perry had 108 buttons. After Xavier used 23 buttons and David used
13 of her buttons, Xavier had twice as many buttons left as David. Perry bought another 32 buttons, he had thrice the number of buttons David had left. How many buttons did Perry have at first?
| |
Xavier |
David |
Perry |
Total |
| Before |
4 u + 23 |
3 u |
6 u - 32 |
108 |
| Change |
- 23 |
- 1 u |
+ 32 |
|
| After |
4 u |
2 u |
6 u |
|
Comparing Xavier
and David in the end |
2 |
1 |
|
|
Comparing Perry
and David in the end |
|
1 |
3 |
|
Number of buttons that Xavier had in the end
= 2 x 2 u
= 4 u
Number of buttons that Perry had in the end
= 3 x 2 u
= 6 u
Total number of buttons at first
= 4 u + 23 + 3 u + 6 u - 32
= 13 u - 9
13 u - 9 = 108
13 u = 108 + 9
13 u = 117
1 u = 117 ÷ 13 = 9
Number of buttons that Perry had at first
= 6 u - 32
= 6 x 9 - 32
= 54 - 32
= 22
Answer(s): 22
