SOLUTION: Two mechanics worked on a car. The first mechanic worked for 15 hours, and the second mechanic worked for 5 hours. Together they charged a total of $1550 . What was the rate charg

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: Two mechanics worked on a car. The first mechanic worked for 15 hours, and the second mechanic worked for 5 hours. Together they charged a total of $1550 . What was the rate charg      Log On


   

Question 830814: Two mechanics worked on a car. The first mechanic worked for 15 hours, and the second mechanic worked for 5 hours. Together they charged a total of $1550 . What was the rate charged per hour by each mechanic if the sum of the two rates was $140 per hour?
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Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Let the rates be R%5B1%5D and R%5B2%5D.
1.R%5B1%5D%2BR%5B2%5D=140
2.15R%5B1%5D%2B5R%5B2%5D=1550
From 1,
R%5B1%5D=140-R%5B2%5D
Substitute into eq. 2,
15%28140-R%5B2%5D%29%2B5R%5B2%5D=1550
2100-15R%5B2%5D%2B5R%5B2%5D=1550
-10R%5B2%5D=-550
highlight%28R%5B2%5D=55%29
Then from eq. 1,
R%5B1%5D%2B55=140
highlight%28R%5B1%5D=85%29