Suppose that y varies jointly with x and x inversely with z and y=540 when w=15, x=30, and z=5. Write the equation that models the relationship.

y=6x/wz

y=x/6wz

y=6wx/z

y=z/6wx

We translate the statements given in the problem into y = k w x / z where k is the constant of proportionality. In this case, from the given data, 540 = k * 15 * 30 / 5; k then is equal to 6. Hence the equation that projects this relationship is C. y = 6 w x/z