Yoko and Emma collected marbles. Yoko gave 30% of her marbles to Emma and as a result, Emma's marbles increased by 25%. If Yoko had 35 marbles left, find the number of marbles Emma should give to Yoko in the end so that both had an equal number of marbles.

	Yoko	Emma	Comparing the change in Emma's marbles
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 marbles that Emma had is repeated.  Make the increase in the number of marbles that Emma had the same. LCM of 3 and 1 = 3

7 u = 35

1 u = 35 ÷ 7 = 5

Number of marbles that Emma had more than Yoko in the end
= 15 u - 7 u
= 8 u

Number of marbles that Emma should give to Yoko so that both had an equal number of marbles in the end
= 8 u ÷ 2
= 4 u
= 4 x 5
= 20

Answer(s): 20