Question 40717
First write the equation:

{{{y = kx/z}}} k is the constant of variation. To find the value of k, substitute the given values of y = 40, x = 20, and z = 2, then solve for k.

{{{40 = 20k/2}}}
{{{40 = 10k}}} Divide both sides by 10.
{{{k = 4}}}

The equation is:
{{{y = 4x/z}}}

Now the second step to find y when x = 60 and z = 4:
Substitute: x = 60 and z = 4.

{{{y = 4(60)/4}}}
{{{y = 60}}}