Wendy has 30% as many erasers as Esther. Esther has 110% as many erasers as Tammy. If Esther gives 45 erasers to Tammy, both will then have an equal number of erasers. Find the average number of erasers the three of them have.

Wendy	Esther	Tammy
3x11	10x11
	11x10	10x10
33 u	110 u	100 u

30% = ³⁰₁₀₀ = ³₁₀
110% = ¹¹⁰₁₀₀= ¹¹₁₀

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

	Esther	Tammy	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 Esther and Tammy have
= 110 u + 100 u
= 210 u

After Esther gives to Tammy, both of them will have the same number of erasers. 

The total number of erasers that Esther and Tammy have remains unchanged.

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

Number of erasers that Esther gives to Tammy
= 110 u - 105 u
= 5 u

5 u = 45

1 u = 45 ÷ 5 = 9

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 9
= 729

Answer(s): 729