y varies directly as x and inversely as the square of z. y. Find y when x = 2 and z = 8

Question

 y varies directly as x and inversely as the square of z. y = 24 when x = 50 and z = 5. Find y when x = 2 and z = 8

Answer 1

If we put y=12(x/z²), then y = 24 for x=50 and  z=5.

Asssuming this is true, we can say that y=12(2/64)=12/32=3/8 for x=2 and z=8.

But there are many different possibilities. So, I guess, there should be some more assumptions.