Risa and Emma had a total of 80 stamps. Emma gave ¹₆ of her stamps to Risa. In return, Risa gave ¹₅ of the total number of stamps that she had to Emma. In the end, each girl had the same number of stamps. How many stamps did Risa have at first?

	Risa	Emma	Total
Before 1	?	6 u	80
Change 1	+ 1 u	- 1 u
After 1	50	5 u	80
Before 2	5 p	5 u	80
Change 2	- 1 p	+ 1 p
After 2	4 p (40)	40	80

Since Emma gave some stamps to Risa and Risa then gave some stamps to Emma, it is an internal transfer of stamps between the two girls. So, the total number of stamps remains unchanged.

Number of stamps that Emma and Risa each had in the end is the same.

Number of stamps that Risa had in the end
= 80 ÷ 2
= 40

Number of stamps that Risa had in the end = 4 p

4 p = 40

1 p = 40 ÷ 4 = 10

Number of stamps that Risa had after receiving some stamps from Emma
= 5 p
= 5 x 10
= 50

Number of stamps that Emma had after giving to Risa
= 80 - 50
= 30

5 u = 30

1 u = 30 ÷ 5 = 6

Number of stamps that Emma had at first
= 6 u
= 6 x 6
= 36

Number of stamps that Risa had at first
= 80 - 36
= 44

Answer(s): 44