The answer you are looking for is X = 4.
To find this, you must first figure out the relationship between 10 and 15. Since 10 is 2/3 of 15, "x" must be 2/3 of 6.
To find "x", divide 6 by 3 to get 2, then 2 by 2 to get 2/3 of 6 (4). Thus meaning X = 4.
I hope this helps!
