Olivia has 30% as many stickers as Shiyun. Shiyun has 140% as many stickers as Pamela. If Shiyun gives 100 stickers to Pamela, both will then have an equal number of stickers. Find the average number of stickers the three of them have.

Olivia	Shiyun	Pamela
3x7	10x7
	7x10	5x10
21 u	70 u	50 u

30% = ³⁰₁₀₀ = ³₁₀
140% = ¹⁴⁰₁₀₀= ⁷₅

The number of stickers that Olivia has is repeated.  Make the number of stickers that Olivia has the same. LCM of 10 and 7 is 70.

	Shiyun	Pamela	Total
Before	70 u	50 u	120 u
Change	- 10 u	+ 10 u
After	60 u	60 u	120 u

Total number of stickers that Shiyun and Pamela have
= 70 u + 50 u
= 120 u

After Shiyun gives to Pamela, both of them will have the same number of stickers. 

The total number of stickers that Shiyun and Pamela have remains unchanged.

Number of stickers that each of them will have
= 120 u ÷ 2
= 60 u

Number of stickers that Shiyun gives to Pamela
= 70 u - 60 u
= 10 u

10 u = 100

1 u = 100 ÷ 10 = 10

Total number of stickers that three of them have
= 120 u + 21 u
= 141 u

Average number of stickers that each of them have
= 141 u ÷ 3
= 47 u
= 47 x 10
= 470

Answer(s): 470