In a kiosk, some rubik's cubes and water guns were on sale. ¹₄ of the items were rubik's cubes. ¹₃ of the rubik's cubes and 290 water guns were sold. There were ¹₉ of the items left in the kiosk. How many rubik's cubes and water guns were there in the kiosk at first?

	Rubik's cubes	Water guns	Total
Comparing rubik's cubes  and water guns at first	1x9 = 9 u	3x9 = 27 u	4x9 = 36 u
Before	3x3 =  9 u		9x4 = 36 u
Change	- 1x3 = - 3 u	- 290	- 8x4 = - 32 u
After	2x3 = 6 u	-2 u	1x4 = 4 u

 
The total number of toys at first is repeated.  Make the total number of toys at first the same. LCM of 4 and 9 is 36.

The number of rubik's cubes at first is repeated.  Make the number of rubik's cubes the same. LCM of 9 and 3 is 9. 

Number of water guns left
= 4 u - 6 u
= -2 u

Number of water guns sold
= 27 u - -2 u
= 29 u

29 u = 290

1 u = 290 ÷ 29 = 10

Number of rubik's cubes and water guns at first
= 36 u
= 36 x 10
= 360

Answer(s): 360