Winnie has 30% as many erasers as Emily. Emily has 110% as many erasers as Min. If Emily gives 30 erasers to Min, both will then have an equal number of erasers. Find the average number of erasers the three of them have.

Winnie	Emily	Min
3x11	10x11
	11x10	10x10
33 u	110 u	100 u

30% = ³⁰₁₀₀ = ³₁₀
110% = ¹¹⁰₁₀₀= ¹¹₁₀

The number of erasers that Winnie has is repeated.  Make the number of erasers that Winnie has the same. LCM of 10 and 11 is 110.

	Emily	Min	Total
Before	110 u	100 u	210 u
Change	- 5 u	+ 5 u
After	105 u	105 u	210 u

Total number of erasers that Emily and Min have
= 110 u + 100 u
= 210 u

After Emily gives to Min, both of them will have the same number of erasers. 

The total number of erasers that Emily and Min have remains unchanged.

Number of erasers that each of them will have
= 210 u ÷ 2
= 105 u

Number of erasers that Emily gives to Min
= 110 u - 105 u
= 5 u

5 u = 30

1 u = 30 ÷ 5 = 6

Total number of erasers that three of them have
= 210 u + 33 u
= 243 u

Average number of erasers that each of them have
= 243 u ÷ 3
= 81 u
= 81 x 6
= 486

Answer(s): 486