There were some silver marbles and green marbles. The marbles were packed into 2 bags. At first, Packet K contained 170 marbles and 30% of them were green marbles. Packet L contained 450 marbles and 60% of them were green marbles. How many silver marbles and green marbles in total must be moved from Packet K to Packet L such that 25% of the marbles in Packet K are silver and 50% of the marbles in Packet L are green?

	Packet K		Packet L
Total	170		450
	Green marbles	Silver marbles	Green marbles	Silver marbles
Before	51	119	270	180
Change	- ?	- ?	+ ?	+ ?
After	3 u	1 u	1 p	1 p

Number of green marbles in Packet K at first
= 30% x 170
= ³⁰₁₀₀ x 170
= 51

Number of silver marbles in Packet K at first
= 170 - 51
= 119

Number of green marbles in Packet L at first
= 60% x 450
= ⁶⁰₁₀₀ x 450
= 270

Number of silver marbles in Packet L at first
= 450 - 270
= 180

Packet K in the end
25% = ²⁵₁₀₀ =¹₄
Green marbles : Silver marbles = 3 : 1

Packet L in the end
50% = ⁵⁰₁₀₀ =¹₂
Green marbles : Silver marbles = 1 : 1

Total number of green marbles = 3 u + 1 p

3 u + 1 p = 51 + 270
3 u + 1 p = 321 

1 p = 321 - 3 u --- (1)

Total number of silver marbles = 1 u + 1 p
1 u + 1 p = 119 + 180
1 u + 1 p = 299

1 p = 299 - 1 u --- (2)

(2) = (1)
299 - 1 u = 321 - 3 u
3 u - 1 u = 321 - 299
2 u = 22

1 u = 22 ÷ 2 = 11

Total number of silver marbles and green marbles that must be moved from Packet K to Packet L
= 170 - 4 u
= 170 - 4 x 11
= 170 - 44
= 126

Answer(s): 126