If 217 red stickers are added, 40% of the stickers will be blue stickers.
If 262 blue stickers are added, 20% of the stickers will be red stickers.

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

	Scenario 1		Scenario 2
	Red	Blue	Red	Blue
Before	3 u - 217	2 u	1 p	4 p - 262
Change	+ 217	No change	No change	+ 262
After	3 u	2 u	1 p	4 p

(a)
40% = ⁴⁰₁₀₀ = ²₅
20% = ²⁰₁₀₀ = ¹₅

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

Number of red stickers at first = 3 u - 217
Number of blue stickers at first = 2 u

Scenario 2
Fraction of the stickers that are blue
= 1 - ¹₅
= ⁴₅

Number of red stickers at first = 1 p
Number of blue stickers at first = 4 p - 262

3 u - 217 = 1 p --- (1)

2 u = 4 p - 262
2 u + 262 = 4 p --- (2)

(1) _{x 4}
12 u - 868 = 4 p --- (3)

(3) = (2)
12 u - 868 = 2 u + 262
12 u - 2 u = 868 + 262
10 u = 1130

1 u = 1130 ÷ 10 = 113

Number of red stickers
= 3 u - 217
= 3 x 113 - 217
= 339 - 217
= 122

(b)
Number of blue stickers
= 2 u
= 2 x 113
= 226

Answer(s): (a) 122; (b) 226