Dana and Nicole collected seashells. Dana gave 60% of her seashells to Nicole and as a result, Nicole's seashells increased by 20%. If Dana had 10 seashells left, find the number of seashells Nicole should give to Dana in the end so that both had an equal number of seashells.

	Dana	Nicole	Comparing the change in Nicole's seashells
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 seashells that Nicole had is repeated.  Make the increase in the number of seashells that Nicole had the same. LCM of 3 and 1 = 3

2 u = 10

1 u = 10 ÷ 2 = 5

Number of seashells that Nicole had more than Dana in the end
= 18 u - 2 u
= 16 u

Number of seashells that Nicole should give to Dana so that both had an equal number of seashells in the end
= 16 u ÷ 2
= 8 u
= 8 x 5
= 40

Answer(s): 40