Shannon and Joelle collected coins. Shannon gave 30% of her coins to Joelle and as a result, Joelle's coins increased by 25%. If Shannon had 70 coins left, find the number of coins Joelle should give to Shannon in the end so that both had an equal number of coins.

	Shannon	Joelle	Comparing the change in Joelle's coins
Before	10x1 = 10 u		4x3 = 12u
Change	- 3x1 = - 3 u	+ 3x1 = + 3 u	+ 1x3 = + 3 u
After	7x1 = 7 u		5x3 = 15 u

30% = ³⁰₁₀₀ = ³₁₀
25% = ²⁵₁₀₀ = ¹₄

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

7 u = 70

1 u = 70 ÷ 7 = 10

Number of coins that Joelle had more than Shannon in the end
= 15 u - 7 u
= 8 u

Number of coins that Joelle should give to Shannon so that both had an equal number of coins in the end
= 8 u ÷ 2
= 4 u
= 4 x 10
= 40

Answer(s): 40