Kathy has 25% as many stamps as Shiyun. Shiyun has 130% as many stamps as Olivia. If Shiyun gives 24 stamps to Olivia, both will then have an equal number of stamps. Find the average number of stamps the three of them have.

Kathy	Shiyun	Olivia
1x13	4x13
	13x4	10x4
13 u	52 u	40 u

25% = ²⁵₁₀₀ = ¹₄
130% = ¹³⁰₁₀₀= ¹³₁₀

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

	Shiyun	Olivia	Total
Before	52 u	40 u	92 u
Change	- 6 u	+ 6 u
After	46 u	46 u	92 u

Total number of stamps that Shiyun and Olivia have
= 52 u + 40 u
= 92 u

After Shiyun gives to Olivia, both of them will have the same number of stamps. 

The total number of stamps that Shiyun and Olivia have remains unchanged.

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

Number of stamps that Shiyun gives to Olivia
= 52 u - 46 u
= 6 u

6 u = 24

1 u = 24 ÷ 6 = 4

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

Average number of stamps that each of them have
= 105 u ÷ 3
= 35 u
= 35 x 4
= 140

Answer(s): 140