Ivory and Barbara collected beads. Ivory gave 60% of her beads to Barbara and as a result, Barbara's beads increased by 20%. If Ivory had 18 beads left, find the number of beads Barbara should give to Ivory in the end so that both had an equal number of beads.

	Ivory	Barbara	Comparing the change in Barbara's beads
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 beads that Barbara had is repeated.  Make the increase in the number of beads that Barbara had the same. LCM of 3 and 1 = 3

2 u = 18

1 u = 18 ÷ 2 = 9

Number of beads that Barbara had more than Ivory in the end
= 18 u - 2 u
= 16 u

Number of beads that Barbara should give to Ivory so that both had an equal number of beads in the end
= 16 u ÷ 2
= 8 u
= 8 x 9
= 72

Answer(s): 72