SOLUTION: A family has two cars. During one particular week, the first car consumed 40 gallons of gas and the second consumed 30 gallons of gas. The two cars drove a combined total of 2150 m

Algebra ->  Equations -> SOLUTION: A family has two cars. During one particular week, the first car consumed 40 gallons of gas and the second consumed 30 gallons of gas. The two cars drove a combined total of 2150 m      Log On


   



Question 1155892: A family has two cars. During one particular week, the first car consumed 40 gallons of gas and the second consumed 30 gallons of gas. The two cars drove a combined total of 2150 miles, and the sum of their fuel efficiencies was 60 miles per gallon. What were the fuel efficiencies of each of the cars that week?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +x+ = the miles / gallon for the 1st car
+60+-+x+ = the miles / gallon for the 2nd car
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+40x+%2B+30%2A%28+60+-+x+%29+=+2150+
+40x+%2B+1800+-+30x+=+2150+
+10x+=+350+
+x+=+35+
+60+-+x+=+60+-+35+
+60+-+x+=+25+
35 miles / gallon for the 1st car
25 miles / gallon for the 2nd car
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check:
+40x+%2B+30%2A%28+60+-+x+%29+=+2150+
+40%2A35+%2B+30%2A25+=+2150+
+1400+%2B+750+=+2150+
+2150+=+2150+
OK