Jean and John collect cards and stickers. John has 80 more stickers than cards. John has 2 times the number of cards Jean has, and Jean has 30% more stickers than John. After Jean gives John all of her cards and John gives Jean 70% of his stickers, John has 12 more cards than stickers. Find the number of stickers Jean has at first.

Jean		John
Stickers	Cards	Stickers	Cards
2.6 u + 104	1 u	2 u + 80	2 u
+ 1.4 u + 56	- 1 u	- 1.4 u - 56	+ 1 u
4 u + 160	0	0.6 u + 24	3 u

100% + 30% = 130% 

130% x 2 u
= ¹³⁰₁₀₀ x 2 u
= 2.6 u

130% x 80
= ¹³⁰₁₀₀ x 80
= 104 

70% x 2 u
= ⁷⁰₁₀₀ x 2 u
= 1.4 u  

70% x 80 
= ⁷⁰₁₀₀ x 80
= 56 

If another 12 stickers are given to John, he will have equal number of stickers and cards in the end.
3 u = 0.6 u + 24 + 12
3 u - 0.6 u = 36
2.4 u = 36

1 u = 36 ÷ 2.4 = 15

Number of stickers that Jean has at first
= 2.6 u + 104
= 2.6 x 15 + 104
= 39 + 104
= 143
 
Answer(s): 143