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

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