In a shop, some flying saucers and rubik's cubes were on sale. ¹₅ of the items were flying saucers. ¹₃ of the flying saucers and 69 rubik's cubes were sold. There were ¹₆ of the items left in the shop. How many flying saucers and rubik's cubes were there in the shop at first?

	Flying saucers	Rubik's cubes	Total
Comparing flying saucers  and rubik's cubes at first	1x6 = 6 u	4x6 = 24 u	5x6 = 30 u
Before	3x2 =  6 u		6x5 = 30 u
Change	- 1x2 = - 2 u	- 69	- 5x5 = - 25 u
After	2x2 = 4 u	1 u	1x5 = 5 u

 
The total number of toys at first is repeated.  Make the total number of toys at first the same. LCM of 5 and 6 is 30.

The number of flying saucers at first is repeated.  Make the number of flying saucers the same. LCM of 6 and 3 is 6. 

Number of rubik's cubes left
= 5 u - 4 u
= 1 u

Number of rubik's cubes sold
= 24 u - 1 u
= 23 u

23 u = 69

1 u = 69 ÷ 23 = 3

Number of flying saucers and rubik's cubes at first
= 30 u
= 30 x 3
= 90

Answer(s): 90