The distance traveled in a car varies directly as the amount of gasoline used. If a car travels 640 miles and uses 32 gallons of gas, find the constant of variation or miles per gallon.
1. 18 mpg
2. 22 mpg
3. 20 mpg
4. 24 mpg
To find the constant of variation or miles per gallon, we can set up a proportion:
miles/gallons = constant of variation
Given that the car traveled 640 miles and used 32 gallons of gas, we can substitute these values into the proportion:
640 miles / 32 gallons = constant of variation
Simplifying, we get:
20 miles/gallon = constant of variation
The constant of variation or miles per gallon is 20 mpg.
Therefore, the correct answer is option 3. 20 mpg.