Emily and Natalie collected erasers. Emily gave 50% of her erasers to Natalie and as a result, Natalie's erasers increased by 30%. If Emily had 27 erasers left, find the number of erasers Natalie should give to Emily in the end so that both had an equal number of erasers.

	Emily	Natalie	Comparing the change in Natalie's erasers
Before	2x3 = 6 u		10x1 = 10u
Change	- 1x3 = - 3 u	+ 1x3 = + 3 u	+ 3x1 = + 3 u
After	1x3 = 3 u		13x1 = 13 u

50% = ⁵⁰₁₀₀ = ¹₂
30% = ³⁰₁₀₀ = ³₁₀

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

3 u = 27

1 u = 27 ÷ 3 = 9

Number of erasers that Natalie had more than Emily in the end
= 13 u - 3 u
= 10 u

Number of erasers that Natalie should give to Emily so that both had an equal number of erasers in the end
= 10 u ÷ 2
= 5 u
= 5 x 9
= 45

Answer(s): 45