How many miles per gallon does a Boeing 747 get?

According to Boeing's Web site, the 747 burns approximately 5 gallons of fuel per mile (12 liters per kilometer). A 747 carrying 500 people is getting 100 miles per gallon per person! A typical car carrying four people gets about 7 miles per gallon per person.
Actually in practice the flight crew considers the weight of the fuel per time flown at a given airspeed. Higher air speeds increase fuel consumption. Strong head winds increase the airspeed but decrease the ground speed and so increase the flight time, but as the fuel is consumed the weight decreases, lower weights decrease fuel consumption . That's why in bad airplane movies people start throwing stuff out of the plane. "Hey! This passenger spends all his time answering stuff on the Bag! He's got no real life, toss him and his laptop out! And don't forget that mime."

Yor arswer.....A typical car carrying four people gets about 7 miles per gallon per person....is wrong based on what I believe that your'e assuming this car gets 28 mpg. The correct answer is (28*4)mpg=112mpg economics favors increased payload.

Non of the answers given throw much light on the question.
Talking about miles across the ground means that the answer would depend on whether there is a head wind or tail wind.
Consequently all operational questions and performance manuals refer to Nautical Air Miles per thousand Pounds of fuel burnt. (NAMPS)
Airliners cruise at their most efficient speed for maximum range. This will maximise the namps.
BUT
+ The heavier they are the lower altitude at which they must cruise and the more power is needed to attain the desired max range speed.Higher fuel burnoff.
+ As fuel is consumed the aircraft weight decreases and so it does not accelerate away from the optimum speed, the power is reduced, ie, fuel burnoff decreases.
+ After some time the aircraft weight has reduced enough that it is capable of climbing either two or four thousand feet. Now while still maintaining that optimum cruise speed the power required is significantley less, the fuel burnoff is less.

The cycle continues, the weight decreases,the power is reduced and eventually the aircraft can again climb.
Now lighter aircraft means less power, less fuel burn off for flight at same, most efficient speed.

This technique maximises the range by flying the aeroplane at its aerodynamically best speed.
Consideration must also be given for the most efficient power setting at which the operate the engine. High power settings give the best operating economy for a jet engine, ie, when the aeroplane is heavy, but overall, airframe considerations and not
engine are the over-riding criteria for long range flight.
Maritime patrol aeroplanes like the P3, when low and slow on patrol shut one or two engines down so that high power settings must be set on the remaining two, for reduced fuel consumption and longer endurance.

The miles are nautical miles and flight fuel is calculated and purchased in kilograms. Volumetric capacity can very from day to day and conversion from American gallons, Imperial gallons, Litres is liable to error and inaccuracy. Aircraft, payload, passenger weights are in Kgs so why not order the fuel by weight. All that needs to be know is specific gravity of the fuel. Cold fuel means more by weight can be fitted into fuel tanks.
Fuel is purchased according to its calorific value. The higher value the greater its cost but the greater NAMPS for each thousand kilos burnt.

Flying into wind DOES not increase aircraft speed , either indicated air speep,(IAS), True Air Speed (TAS) or Ground Speed. High altitude winds, the jet streams, blow only from west to east in both hemispheres and can reach over 220 knots. (Nautical miles per hour).
On the nose that could make for massive increase in the total fuel burnt going from A to B as the flight time could be increased by several hours.

This is a basic explanation for range flying , ie, how far.(Distance)
Endurance is about how long, (Time) and that is a different technique flown at different speeds at different altitudes for different weights.
Every thing in the operation of airliners is about optimising performance for a particular weight, which is changing every minute as fuel is burnt.
cowboy

That's what I was going to say..What an idiot. He's trying to show the economic benefit of air travel over automobile, but any typical car now gets 25+mpg, so with four passengers it comes out exactly the same...100mpg for each passenger

I get 5.2 mile per gallon in mine.

I think I'm going to agree with @steve635. it's a bit of a confusing question because instead of using miles per gallon, we're using gallons per mile, right? in that case if a boeing 747 gets 5 gpm than it gets .2 mpg (w/ 500 passengers), still with me? with a car (assuming a standard sedan) that gets 28 mpg for 4 passengers, we get 28 mile (w/ 4 passengers). intuitively we would like to divide at this point because it seems as though 28mpg=4 people, however by adding a person to your car you get better mileage. by yourself you get 28 mpg, but when you have another person in the car you have both traveled 28 miles giving you both 28 miles, 28+28=56 right? so we have to do the same thing with both the plane and the car. 28*4=112 500*.2=100. Basically the moral of the story is that planes aren't fuel efficient.