Final answer:
The correct representation for 'fewer than 7 gallons of gas' in inequality form using the variable 'f' is 'f < 7'.
Step-by-step explanation:
The student has provided the context and is seeking to express an inequality that states there are fewer than 7 gallons of gas in the tank. To represent this mathematically, we use a variable, which in this case is f for the number of gallons in the tank. The appropriate inequality to represent 'fewer than 7 gallons' is f < 7. This means the amount of gas in the tank is less than 7 gallons, but it does not give us a lower limit, so the tank could be empty or have any volume of gas up to but not including 7 gallons.