Tammy and Nora collected stickers. Tammy gave 25% of her stickers to Nora and as a result, Nora's stickers increased by 30%. If Tammy had 81 stickers left, find the number of stickers Nora should give to Tammy in the end so that both had an equal number of stickers.

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

9 u = 81

1 u = 81 ÷ 9 = 9

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

Number of stickers that Nora should give to Tammy so that both had an equal number of stickers in the end
= 4 u ÷ 2
= 2 u
= 2 x 9
= 18

Answer(s): 18