Fiona and Tina collected erasers. Fiona gave 30% of her erasers to Tina and as a result, Tina's erasers increased by 10%. If Fiona had 70 erasers left, find the number of erasers Tina should give to Fiona in the end so that both had an equal number of erasers.

	Fiona	Tina	Comparing the change in Tina's erasers
Before	10x1 = 10 u		10x3 = 30u
Change	- 3x1 = - 3 u	+ 3x1 = + 3 u	+ 1x3 = + 3 u
After	7x1 = 7 u		11x3 = 33 u

30% = ³⁰₁₀₀ = ³₁₀
10% = ¹⁰₁₀₀ = ¹₁₀

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

7 u = 70

1 u = 70 ÷ 7 = 10

Number of erasers that Tina had more than Fiona in the end
= 33 u - 7 u
= 26 u

Number of erasers that Tina should give to Fiona so that both had an equal number of erasers in the end
= 26 u ÷ 2
= 13 u
= 13 x 10
= 130

Answer(s): 130