If 256 blue stickers are added, 40% of the stickers will be green stickers.
If 135 green stickers are added, 25% of the stickers will be blue stickers.

1. How many blue stickers are there? 
2. How many green stickers are there? 

	Scenario 1		Scenario 2
	Blue	Green	Blue	Green
Before	3 u - 256	2 u	1 p	3 p - 135
Change	+ 256	No change	No change	+ 135
After	3 u	2 u	1 p	3 p

(a)
40% = ⁴⁰₁₀₀ = ²₅
25% = ²⁵₁₀₀ = ¹₄

Scenario 1
Fraction of the stickers that are blue
= 1 - ²₅
= ³₅

Number of blue stickers at first = 3 u - 256
Number of green stickers at first = 2 u

Scenario 2
Fraction of the stickers that are green
= 1 - ¹₄
= ³₄

Number of blue stickers at first = 1 p
Number of green stickers at first = 3 p - 135

3 u - 256 = 1 p --- (1)

2 u = 3 p - 135
2 u + 135 = 3 p --- (2)

(1) _{x 3}
9 u - 768 = 3 p --- (3)

(3) = (2)
9 u - 768 = 2 u + 135
9 u - 2 u = 768 + 135
7 u = 903

1 u = 903 ÷ 7 = 129

Number of blue stickers
= 3 u - 256
= 3 x 129 - 256
= 387 - 256
= 131

(b)
Number of green stickers
= 2 u
= 2 x 129
= 258

Answer(s): (a) 131; (b) 258