Adam has some green stickers and blue stickers.
If Adam gives away 28 green stickers,
the green stickers will be 20% as many as the blue stickers.
If Adam gives away 100 blue stickers,
the green stickers will be 80% as many as the blue stickers.

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

	Scenario 1		Scenario 2
	Green	Blue	Green	Blue
Before	1 u + 28	5 u	4 p	5 p + 100
Change	- 28	No change	No change	- 100
After	1 u	5 u	4 p	5 p

(a)
20% = ²⁰₁₀₀ = ¹₅
80% = ⁸⁰₁₀₀ = ⁴₅

Scenario 1
Number of green stickers at first = 1 u + 28
Number of blue stickers at first = 5 u

Scenario 2
Number of green stickers at first = 4 p
Number of blue stickers at first = 5 p + 100

1 u + 28 = 4 p --- (1)
5 u = 5 p + 100 --- (2)

(1) _{x 5}
5 u + 140 = 20 p
5 u = 20 p - 140 --- (3)

(3) = (2)
20 p - 140 = 5 p + 100
20 p - 5 p = 140 + 100
15 p = 240

1 p = 240 ÷ 15 = 16

Number of green stickers
= 4 p
= 4 x 16
= 64

(b)
Number of blue stickers at first
= 5 p + 100
= 5 x 16 + 100
= 80 + 100
= 180

Answer(s): (a) 64; (b) 180