Winnie has 25% as many pens as Eva. Eva has 130% as many pens as Joelle. If Eva gives 72 pens to Joelle, both will then have an equal number of pens. Find the average number of pens the three of them have.

Winnie	Eva	Joelle
1x13	4x13
	13x4	10x4
13 u	52 u	40 u

25% = ²⁵₁₀₀ = ¹₄
130% = ¹³⁰₁₀₀= ¹³₁₀

The number of pens that Winnie has is repeated.  Make the number of pens that Winnie has the same. LCM of 4 and 13 is 52.

	Eva	Joelle	Total
Before	52 u	40 u	92 u
Change	- 6 u	+ 6 u
After	46 u	46 u	92 u

Total number of pens that Eva and Joelle have
= 52 u + 40 u
= 92 u

After Eva gives to Joelle, both of them will have the same number of pens. 

The total number of pens that Eva and Joelle have remains unchanged.

Number of pens that each of them will have
= 92 u ÷ 2
= 46 u

Number of pens that Eva gives to Joelle
= 52 u - 46 u
= 6 u

6 u = 72

1 u = 72 ÷ 6 = 12

Total number of pens that three of them have
= 92 u + 13 u
= 105 u

Average number of pens that each of them have
= 105 u ÷ 3
= 35 u
= 35 x 12
= 420

Answer(s): 420