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An electrician charges a $40 fee to make a house call plus an hourly rate for labor. If the total bill that takes 2 hours comes to $99 what is the electrician hourly labor rate?

User Ecton
by
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1 Answer

8 votes
Answer $29.50
Reason
You can use the formula y=mx+b for this
We know y is the total bill of $99
We know b is the $40 fee (y intercept or starting point)
We know x is 2 hours
We are looking for m or rate
Substitute numbers for letters in formula
99= m(2) +40
Subtract 40 from both sides to isolate m
59=2m
Divide both sides by 2 to solve for m
M=$29.50
We can prove our answer by inserting our answer for “m” in the formula
99=29.50x2+40
99=99
Answer is correct
User KentH
by
4.9k points