Diana and Hazel collected stamps. Diana gave 30% of her stamps to Hazel and as a result, Hazel's stamps increased by 10%. If Diana had 28 stamps left, find the number of stamps Hazel should give to Diana in the end so that both had an equal number of stamps.

	Diana	Hazel	Comparing the change in Hazel's stamps
Before	10x1 = 10 u		10x3 = 30u
Change	- 3x1 = - 3 u	+ 3x1 = + 3 u	+ 1x3 = + 3 u
After	7x1 = 7 u		11x3 = 33 u

30% = ³⁰₁₀₀ = ³₁₀
10% = ¹⁰₁₀₀ = ¹₁₀

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

7 u = 28

1 u = 28 ÷ 7 = 4

Number of stamps that Hazel had more than Diana in the end
= 33 u - 7 u
= 26 u

Number of stamps that Hazel should give to Diana so that both had an equal number of stamps in the end
= 26 u ÷ 2
= 13 u
= 13 x 4
= 52

Answer(s): 52