y is 15 :)
Explanation:
If you divide 3/2, you get 1.5. 15/10 is also get 1.5
Another way of doing this is by cross multiplying. Multiply 3 by 10 to get 30 on the right side of the equation. Multiply 2 by y to get 2y. Then divide both sides by 2 and you get y = 15.
