Jul

06

2008

Jun

22

2008

Courtesy Art OglesbyGuess the answer to this word problem before doing the math.

- Car A (a compact) gets 34 mpg
- Car B (a hybrid) gets 54 mpg
- Car C (an S.U.V.) gets 18 mpg
- Car D (a sedan) gets 28 mpg

Which would save more gasoline?

- (a)replacing Car A with Car B
- (b)replacing Car C with Car D
- (c)both would save the same

I drive my car about 10,000 miles each year. One way to look at this problem would be to calculate how many gallons of gas each of the four cars would use to go 10,000 miles. Can you do the math? If gas costs $4 per gallon what is the cost for each car to go the 10,000 miles?

I will do the math for my Geo Metro as an example. It now has over 100,000 miles on it. Until recently it got 50 miles per gallon. Two gallons would take me 100 miles, 20 gallons would take 1000 miles. 100,000 miles would take 2000 gallons. With $4 gas that 2000 gallons would cost $8000.

I once owned a Ford pickup truck. If it got 20 mpg and if I drove it 100,000 miles I would need 5000 gallons which would cost me $20,000. By replacing my pickup with the Metro I use less than half the gas and save over $1000 a year. I used to commute to work and put on 30,000 miles per year. That figures out to a $36,000 saving over 10 years.

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