Kathy and Gem collected seashells. Kathy gave 30% of her seashells to Gem and as a result, Gem's seashells increased by 25%. If Kathy had 42 seashells left, find the number of seashells Gem should give to Kathy in the end so that both had an equal number of seashells.

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

7 u = 42

1 u = 42 ÷ 7 = 6

Number of seashells that Gem had more than Kathy in the end
= 15 u - 7 u
= 8 u

Number of seashells that Gem should give to Kathy so that both had an equal number of seashells in the end
= 8 u ÷ 2
= 4 u
= 4 x 6
= 24

Answer(s): 24