Julie and Nora collected erasers. Julie gave 25% of her erasers to Nora and as a result, Nora's erasers increased by 30%. If Julie had 72 erasers left, find the number of erasers Nora should give to Julie in the end so that both had an equal number of erasers.

	Julie	Nora	Comparing the change in Nora'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 Nora had is repeated.  Make the increase in the number of erasers that Nora had the same. LCM of 1 and 3 = 3

9 u = 72

1 u = 72 ÷ 9 = 8

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

Number of erasers that Nora should give to Julie so that both had an equal number of erasers in the end
= 4 u ÷ 2
= 2 u
= 2 x 8
= 16

Answer(s): 16