Charlie and Gabriel had 132 staplers together. Charlie had 28 more staplers than Gabriel. Both of them sold some of their staplers. Gabriel sold 30% less staplers than what Charlie sold. In the end, Gabriel had half as many staplers left as Charlie. How many staplers had Charlie left?

	Charlie (1)	Gabriel (2)	Make p the same (2)x2 = (3)
Comparing Charlie and Gabriel at first	28 more
Before	80	52	104
Change	- 10 u	- 7 u	- 14 u
After	2 p	1 p	2 p

Number of staplers that Gabriel had at first
= (132 - 28) ÷ 2
= 104 ÷ 2
= 52

Number of staplers that Charlie had at first
= 52 + 28
= 80

Number of staplers that Gabriel sold in percent
= 100% - 30%
= 70%

70% = ⁷⁰₁₀₀ = ⁷₁₀

Make p the same.

(1) = (3)
80 - 10 u = 104 - 14 u
14 u - 10 u = 104 - 80
4 u = 24

1 u = 24 ÷ 4 = 6

Number of staplers that Charlie had left
= 80 - 10 u
= 80 - 10 x 6
= 80 - 60
= 20

Answer(s): 20