Lynn and Lucy collected erasers. Lynn gave 25% of her erasers to Lucy and as a result, Lucy's erasers increased by 30%. If Lynn had 63 erasers left, find the number of erasers Lucy should give to Lynn in the end so that both had an equal number of erasers.

	Lynn	Lucy	Comparing the change in Lucy's erasers
Before	4x3 = 12 u		10x1 = 10u
Change	- 1x3 = - 3 u	+ 1x3 = + 3 u	+ 3x1 = + 3 u
After	3x3 = 9 u		13x1 = 13 u

25% = ²⁵₁₀₀ = ¹₄
30% = ³⁰₁₀₀ = ³₁₀

The increase in the number of erasers that Lucy had is repeated.  Make the increase in the number of erasers that Lucy had the same. LCM of 1 and 3 = 3

9 u = 63

1 u = 63 ÷ 9 = 7

Number of erasers that Lucy had more than Lynn in the end
= 13 u - 9 u
= 4 u

Number of erasers that Lucy should give to Lynn so that both had an equal number of erasers in the end
= 4 u ÷ 2
= 2 u
= 2 x 7
= 14

Answer(s): 14