5. Mark works at a job where his pay varies directly with the number of hours he works. Her pay for 25 hours is $312.50. Write a direction variation equation relating Mark's pay y to the hours he worked x.

y = 12.5x

Step-by-step explanation:

Let the direct variation equation relating Mark's pay y to the hours he worked x is y = kx ... (1), where k is a constant.

Now, it is given that her pay for 25 hours is $312.50.

Hence, putting x = 25 and corresponding value of y = 312.50 in the equation (1) we get, 312.5 = 25k, ⇒ k = 12.5.

Therefore, equation (1) becomes y = 12.5x. (Answer)