There were some green stickers and white stickers. The stickers were packed into 2 bags. At first, Box N contained 220 stickers and 30% of them were white stickers. Box P contained 650 stickers and 60% of them were white stickers. How many green stickers and white stickers in total must be moved from Box N to Box P such that 20% of the stickers in Box N are green and 50% of the stickers in Box P are white?

	Box N		Box P
Total	220		650
	White stickers	Green stickers	White stickers	Green stickers
Before	66	154	390	260
Change	- ?	- ?	+ ?	+ ?
After	4 u	1 u	1 p	1 p

Number of white stickers in Box N at first
= 30% x 220
= ³⁰₁₀₀ x 220
= 66

Number of green stickers in Box N at first
= 220 - 66
= 154

Number of white stickers in Box P at first
= 60% x 650
= ⁶⁰₁₀₀ x 650
= 390

Number of green stickers in Box P at first
= 650 - 390
= 260

Box N in the end
20% = ²⁰₁₀₀ =¹₅
White stickers : Green stickers = 4 : 1

Box P in the end
50% = ⁵⁰₁₀₀ =¹₂
White stickers : Green stickers = 1 : 1

Total number of white stickers = 4 u + 1 p

4 u + 1 p = 66 + 390
4 u + 1 p = 456 

1 p = 456 - 4 u --- (1)

Total number of green stickers = 1 u + 1 p
1 u + 1 p = 154 + 260
1 u + 1 p = 414

1 p = 414 - 1 u --- (2)

(2) = (1)
414 - 1 u = 456 - 4 u
4 u - 1 u = 456 - 414
3 u = 42

1 u = 42 ÷ 3 = 14

Total number of green stickers and white stickers that must be moved from Box N to Box P
= 220 - 5 u
= 220 - 5 x 14
= 220 - 70
= 150

Answer(s): 150