Zoe has 25% as many erasers as Roshel. Roshel has 130% as many erasers as Eva. If Roshel gives 30 erasers to Eva, both will then have an equal number of erasers. Find the average number of erasers the three of them have.

Zoe	Roshel	Eva
1x13	4x13
	13x4	10x4
13 u	52 u	40 u

25% = ²⁵₁₀₀ = ¹₄
130% = ¹³⁰₁₀₀= ¹³₁₀

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

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

Total number of erasers that Roshel and Eva have
= 52 u + 40 u
= 92 u

After Roshel gives to Eva, both of them will have the same number of erasers. 

The total number of erasers that Roshel and Eva have remains unchanged.

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

Number of erasers that Roshel gives to Eva
= 52 u - 46 u
= 6 u

6 u = 30

1 u = 30 ÷ 6 = 5

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

Average number of erasers that each of them have
= 105 u ÷ 3
= 35 u
= 35 x 5
= 175

Answer(s): 175