Suppose that the distance a car travels varies directly with the amount of gasoline it uses. A certain car uses 25 gallons of gasoline to travel 800 miles. If the car travels 608 miles, how much gasoline does it need?
gallons
Solution
Step 1 :D = k * G
Step 2 :800 = k * 25
Step 3 :k = 800/25
Step 4 :k = 32
Step 5 :608 = 32 * G
Step 6 :G = 608/32
Step 7 :G = 19
Step 8 :\(\boxed{19}\) gallons of gasoline are needed to travel 608 miles.