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

	Jean	Emily	Comparing the change in Emily's stamps
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 stamps that Emily had is repeated.  Make the increase in the number of stamps that Emily had the same. LCM of 3 and 1 = 3

7 u = 35

1 u = 35 ÷ 7 = 5

Number of stamps that Emily had more than Jean in the end
= 15 u - 7 u
= 8 u

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

Answer(s): 20