SOLUTION: This is a tough one: A family has two cars. The first car gets 20 miles per gallon, and the second car gets 35 mpg. During one particular week, the two cars drove a combined total

Algebra ->  Expressions-with-variables -> SOLUTION: This is a tough one: A family has two cars. The first car gets 20 miles per gallon, and the second car gets 35 mpg. During one particular week, the two cars drove a combined total       Log On


   



Question 455335: This is a tough one: A family has two cars. The first car gets 20 miles per gallon, and the second car gets 35 mpg. During one particular week, the two cars drove a combined total of 1850 miles for a total gas consumption of 70 gallons. How many gallons were consumed by each of the two cars that week?
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
A family has two cars. The first car gets 20 miles per gallon, and the second car gets 35 mpg. During one particular week, the two cars drove a combined total of 1850 miles for a total gas consumption of 70 gallons. How many gallons were consumed by each of the two cars that week?
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m = miles on 1st car
m/20 + (1850-m)/35 = 70
7m + 4(1850-m) = 9800
7m - 4m + 7400 = 9800
3m = 2400
m = 800 miles using 40 gallons
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2nd car went 1050 miles used 30 gallons