Natalie and Jade collected marbles. Natalie gave 60% of her marbles to Jade and as a result, Jade's marbles increased by 20%. If Natalie had 20 marbles left, find the number of marbles Jade should give to Natalie in the end so that both had an equal number of marbles.

	Natalie	Jade	Comparing the change in Jade's marbles
Before	5x1 = 5 u		5x3 = 15u
Change	- 3x1 = - 3 u	+ 3x1 = + 3 u	+ 1x3 = + 3 u
After	2x1 = 2 u		6x3 = 18 u

60% = ⁶⁰₁₀₀ = ³₅
20% = ²⁰₁₀₀ = ¹₅

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

2 u = 20

1 u = 20 ÷ 2 = 10

Number of marbles that Jade had more than Natalie in the end
= 18 u - 2 u
= 16 u

Number of marbles that Jade should give to Natalie so that both had an equal number of marbles in the end
= 16 u ÷ 2
= 8 u
= 8 x 10
= 80

Answer(s): 80