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

	Packet Q		Packet R
	Apple	Vanilla	Apple	Vanilla
	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 Q
= 7 u + 3 u
= 10 u

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

Number of apple mochi balls in Packet R
= 125% x 7 u
=  ¹²⁵₁₀₀ x 7 u
= 8.75 u

Number of apple mochi balls in Packet R
= 40 u - 8.75 u
= 31.25 u

Number of vanilla mochi balls to be transferred from Packet R to Packet Q
= 7 u - 3 u
= 4 u

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

Answer(s): 12.8%