Container D contains 13 green balls and 14 pink balls. Container E contains 117 green balls and 52 pink balls. How many pink balls and green balls must be transferred from Container E to put into Container D so that 50% of the balls in Container A are green and 70% of the balls in Container E are green?

	Container D		Container E
	Green balls	Pink balls	Green balls	Pink balls
Before	13	14	117	52
Change	+ ?	+ ?	- ?	- ?
After	1 u	1 u	7 p	3 p

50% = ⁵⁰₁₀₀ = 12

70% = ⁷⁰₁₀₀ = 710

Number of green balls = 13 + 117 = 130 

Number of pink balls = 14 + 52 = 66 

1 u + 7 p = 130 --- (1)

1 u + 3 p = 66 ---(2)

(1) - (2)
(1 u + 7 p) - (1 u + 3 p) = 130 - 66
7 p - 3 p = 64
4 p = 64

1 p = 64 ÷ 4 = 16

From (2):
1 u + 3 p = 66
1 u + 3 x 16 = 66
1 u + 48 = 66

1 u = 66 - 48 = 18

Number of pink balls to be transferred from Container E to Container D
= 52 - 3 p
= 52 - 3 x 16
= 52 - 48
= 4

Number of green balls to be transferred from Container E to Container D
= 1 u - 13
= 18 - 13
= 5

Total number of pink and green balls to be transferred from Container E to Container D
= 4 + 5
= 9

Answer(s): 9