Yoko and Risa have some shortbreads each. If Yoko gives Risa 21 shortbreads, Yoko will have ¹₄ as many shortbreads as Risa. If Yoko gives Risa 9 shortbreads, they will have an equal number of shortbreads. How many shortbreads does Risa have at first?

	Case 1		Case 2
	Yoko	Risa	Yoko	Risa
Before	1 u + 21	4 u - 21	2.5 u + 9	2.5 u - 9
Change	- 21	+ 21	- 9	+ 9
After	1 u	4 u	2.5 u	2.5 u

Total number of shortbreads that Yoko and Risa have
= 1 u + 4 u
= 5 u 

Number of shortbreads that Yoko and Risa each has in the end is the same.

Number of shortbreads that Yoko and Risa each has in the end in Case 2
= 5 u ÷ 2
= 2.5 u

Number of shortbreads that Yoko had at first is the same in Case 1 and Case 2.

2.5 u + 9 = 1 u + 21
2.5 u - 1 u = 21 - 9
0.5 u = 12

1 u = 12 ÷ 0.5 = 24

Number of shortbreads that Risa has
= 4 u - 21
= 4 x 24 - 21
= 96 - 21
= 75

Answer(s): 75