The answer depends on the relationship between x and y. But since you have not bothered to share that crucial bit of information, I cannot provide a more useful answer.
76
y = 6
15 (x = 135)
x = 14
3
13 ? 15
y = 10. easy!
15
that means the value of x is same as the value of y
y and ½z
Any value
y = 10x where x = 478 y = 10 x 478 = 4780