Glen and Cody had 246 notebooks together. Cody had 2 less notebooks than Glen. Both of them sold some of their notebooks. Cody sold 10% more notebooks than what Glen sold. In the end, Cody had half as many notebooks left as Glen. How many notebooks had Cody left?

	Glen (1)	Cody (2)	Make p the same (2)x2 = (3)
Comparing Glen and Cody at first	2 more
Before	124	122	244
Change	- 10 u	- 11 u	- 22 u
After	2 p	1 p	2 p

Number of notebooks that Cody had at first
= (246 - 2) ÷ 2
= 244 ÷ 2
= 122

Number of notebooks that Glen had at first
= 122 + 2
= 124

Number of notebooks that Cody sold in percent
= 100% + 10%
= 110%

110% = ¹¹⁰₁₀₀ = ¹¹₁₀

Make p the same.

(1) = (3)
124 - 10 u = 244 - 22 u
22 u - 10 u = 244 - 124
12 u = 120

1 u = 120 ÷ 12 = 10

Number of notebooks that Cody had left
= 122 - 11 u
= 122 - 11 x 10
= 122 - 110
= 12

Answer(s): 12