A car repair shop charged $80 per hour for labor and $210 for the parts of a car. If the total cost was $490, how many hours did it take to repair the car?
Here total cost is $490 and cost of the parts is $210.
So, total repair charge = $490-$210 = $280.
Repair shop charges $80 for 1 hour labor.
Therefore no. of hours required to repair the car =
Subtract the cost of parts from total cost. This will leave us with the cost of labour.
#rArr$490-$210=$280larr" cost of labour"#
Dividing cost of labour by $80 will give the number of hours spent on repairing the car.
#rArr280/80=3.5larr" number of hours"#
#3.5" or " 3 1/2" hours spent on repairing the car"#