SOLUTION: In a family there are two cars. In a given week, the first car gets an average of 15 miles per gallon, and the second car gets 40 miles per gallon. The two cars combined drive a to
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-> SOLUTION: In a family there are two cars. In a given week, the first car gets an average of 15 miles per gallon, and the second car gets 40 miles per gallon. The two cars combined drive a to
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Question 105531: In a family there are two cars. In a given week, the first car gets an average of 15 miles per gallon, and the second car gets 40 miles per gallon. The two cars combined drive a total of 65 miles in that week, for a total gas consumption of 1600 gallons. How many gallons were consumed by each of the two cars that week?
You can put this solution on YOUR website! Let x=miles driven by the 15 mpg car
Then 15x=amount of gas used by the 15 mpg car
And 65-x=miles driven by the 40 mpg car
Then 40(65-x)=amount of gas used by the 40 mpg car
Now we are told that together the two cars use 1600 gallons. So our equation to solve is:
15x+40(65-x)=1600 get rid of parens
15x+2600-40x=1600 subtract 2600 from both sides
15x+2600-2600-40x=1600-2600 collect like terms
-25x=-1000 divide both sides by -25
x=40 miles--------------------miles driven by the 15 mpg car
65-x=65-40=25 miles -----------miles driven by the 40 mpg car
CK
40*15+25*40=1600
600+1000=1600
1600=1600
Hope this helps----ptaylor
