Question

Suppose that y varies directly with x and inversely with z, and y = 4 when x = 8 and z = 14. Find z when x = 36 and y = 6. First, what is the equation of variation? y =



What is the value of k?

Answer 1

y=kx/z is the equation of variation.
4=8k/14, so k=4×14/8=7. Therefore k=7. So y=7x/z. When x=36 and y=6, 6=252/z, z=252/6=42.

Answer 2

Answer:y=kx/z

                 k=7

                 z=42