Let h equal the number of hours the electrician works.
We can write the equation like this:
90h + 60 = 600
Solve for h.
90h + 60 = 600
~Subtract 60 to both sides
90h + 60 - 60 = 600 - 60
~Simplify
90h = 540
~Divide 90 to both sides
90h/90 = 540/90
~Simplify
h = 6
Therefore, the electrician work for 6 hours.
The correct answer is Option 1.
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