Zara and Gillian collected stamps. Zara gave 60% of her stamps to Gillian and as a result, Gillian's stamps increased by 20%. If Zara had 16 stamps left, find the number of stamps Gillian should give to Zara in the end so that both had an equal number of stamps.

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

2 u = 16

1 u = 16 ÷ 2 = 8

Number of stamps that Gillian had more than Zara in the end
= 18 u - 2 u
= 16 u

Number of stamps that Gillian should give to Zara so that both had an equal number of stamps in the end
= 16 u ÷ 2
= 8 u
= 8 x 8
= 64

Answer(s): 64