Peter and Rael had 84 stickers in total. Peter had 28 stickers less than Rael at first. After Peter and Rael played a game with Jade, Peter had ¹₅ as many stickers as Rael. If Peter lost as many stickers as Rael to Jade, find the number of stickers that Rael lost to Jade.

	Peter	Rael	Difference
Before	1 u	1 u + 28	28
Change	- ?	- ?
After	1 p	5 p	4 p

Total number of stickers at first
= 1 u + 1 u + 28 
= 2 u + 28

2 u + 28 = 84
2 u = 84 - 28
2 u = 56

1 u = 56 ÷ 2 = 28

Since Peter lost the same number of stickers as Rael, the difference in the number of stickers between Peter and Rael at first and in the end remains the same.

Difference in the number of stickers in the end
= 5 p - 1 p
= 4 p

4 p = 28

1 p = 28 ÷ 4 = 7

Number of stickers that Peter lost to Jade
= 1 u - 1 p
= 28 - 1 x 7
= 28 - 7
= 21

Since Rael lost the same number of stickers as Peter, the number of stickers that each lost to Jade is the same.

Number of stickers that Rael lost = 21

Answer(s): 21