The total cost of hiring Plumbing Service is given by the equation C = 50t + 70, where C is the total cost in dollar and t is the time in hours.
So, $ 70 is the fixed price and $50 is the rate of charge per hour for the service.
Now if in the next month the rate of charge per hour for the service increased to $60 and the initial charge remains the same then the equation for the total cost of hiring Plumbing Service will become C = 60t + 70. (Answer)
