Zoe and Carl collect pens and stickers. Carl has 100 less pens than stickers. Carl has 4 times the number of pens Zoe has, and Zoe has 30% more stickers than Carl. After Zoe gives Carl all of her pens and Carl gives Zoe 70% of his stickers, Carl has 27 more pens than stickers. Find the number of stickers Zoe has at first.

Zoe		Carl
Stickers	Pens	Stickers	Pens
5.2 u + 130	1 u	4 u + 100	4 u
+ 2.8 u + 70	- 1 u	- 2.8 u - 70	+ 1 u
8 u + 200	0	1.2 u + 30	5 u

100%+ 30% = 130% 

130% x 4 u
= ¹³⁰₁₀₀ x 4 u
= 5.2 u

130% x 100
= ¹³⁰₁₀₀ x 100
= 130 

70% x 4 u
= ⁷⁰₁₀₀ x 4 u
= 2.8 u  

70% x 100 
= ⁷⁰₁₀₀ x 100
= 70 

If another 27 stickers are given to Carl, he will have equal number of stickers and pens in the end.
5 u = 1.2 u + 30 + 27
5 u - 1.2 u = 57
3.8 u = 57

1 u = 57 ÷ 3.8 = 15

Number of stickers that Zoe has at first
= 5.2 u + 130
= 5.2 x 15 + 130
= 78 + 130
= 208
 
Answer(s): 208