70% of the mochi balls in Packet W were blueberry mochi balls and the rest were apricot mochi balls. Packet X had 25% more blueberry mochi balls than Packet W and four times as many mochi balls than the total number of mochi balls in Packet W. Find the percentage of the apricot mochi balls in Packet X that would need to be transferred into Packet W, so that there were an equal number of blueberry and apricot mochi balls in Packet W.

	Packet W		Packet X
	Blueberry	Apricot	Blueberry	Apricot
	10 u		40 u
Before	7 u	3 u	8.75 u	31.25 u
Change		+ 4 u		- 4 u
After	7 u	7 u	8.75 u	27.25 u

70% = ⁷⁰₁₀₀ = ⁷₁₀
100 %+ 25% = 125%

 Total number of mochi balls in Packet W
= 7 u + 3 u
= 10 u

Total number of mochi balls in Packet X
= 4 x 10 u 
= 40 u

Number of blueberry mochi balls in Packet X
= 125% x 7 u
=  ¹²⁵₁₀₀ x 7 u
= 8.75 u

Number of blueberry mochi balls in Packet X
= 40 u - 8.75 u
= 31.25 u

Number of apricot mochi balls to be transferred from Packet X to Packet W
= 7 u - 3 u
= 4 u

Percentage of mochi balls to be transferred from Packet X
= ⁴_31.25 x 100%
= 12.8%

Answer(s): 12.8%