Nicole and Daniel collect coins and pens. Daniel has 80 less coins than pens. Daniel has 3 times the number of coins Nicole has, and Nicole has 40% more pens than Daniel. After Nicole gives Daniel all of her coins and Daniel gives Nicole 70% of his pens, Daniel has 38 more coins than pens. Find the number of pens Nicole has at first.

Nicole		Daniel
Pens	Coins	Pens	Coins
4.2 u + 112	1 u	3 u + 80	3 u
+ 2.1 u + 56	- 1 u	- 2.1 u - 56	+ 1 u
6.3 u + 168	0	0.9 u + 24	4 u

100%+ 40% = 140% 

140% x 3 u
= ¹⁴⁰₁₀₀ x 3 u
= 4.2 u

140% x 80
= ¹⁴⁰₁₀₀ x 80
= 112 

70% x 3 u
= ⁷⁰₁₀₀ x 3 u
= 2.1 u  

70% x 80 
= ⁷⁰₁₀₀ x 80
= 56 

If another 38 pens are given to Daniel, he will have equal number of pens and coins in the end.
4 u = 0.9 u + 24 + 38
4 u - 0.9 u = 62
3.1 u = 62

1 u = 62 ÷ 3.1 = 20

Number of pens that Nicole has at first
= 4.2 u + 112
= 4.2 x 20 + 112
= 84 + 112
= 196
 
Answer(s): 196