SOLUTION: An old machine produces 30 components per hour and a new machine produces 40 components per hour. Yesterday both machines were in operation for different periods of time. If 545 co

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Question 1161400: An old machine produces 30 components per hour and a new machine produces 40 components per hour. Yesterday both machines were in operation for different periods of time. If 545 components were produced when the to total number of hours of operation was 15 hours, determine how many hours each machine was operating.
Answer by ikleyn(52824) About Me  (Show Source):
You can put this solution on YOUR website!
.

Let x be the number of hours the new machine was in operation.

Then the old machine was  (15-x) hours in operation.


Your basic equation is

    30*(15-x) + 40x = 545.


From the equation,

    x = %28545-30%2A15%29%2F%2840-30%29 = 9.5   hours.


ANSWER.  The new machine was 9.5 hours in operation;  the old machine  (15-9.5) = 5.5 hours.


CHECK.  30*5.5 + 40*9.5 = 545 components.    ! Precisely correct !

Solved.