The variable of z

Question

The variable z is directly proportional to x, and inversely proportional to Y. When x is 3 and Y is 6, z has the value 9.5. What is the value of z when x=8 and Y=12

round to at least the thousandths place if needed.

Answer 1

z = kx/y

9.5 = k*3/6 = (1/2)k

19 = k

z = 19*x/y

SO then z = 19*8/12 = 19 * 2/3 = 38/3