This demonstration is a good one. Using balloons attached to the exhaust, we are able to easily see how much air the engine is using in real time. Besides just being interesting math, this information also shows how long it would take for a car to eat up all the air in your garage, suffocating you if the carbon monoxide hadn't taken you out first.
For example, a Bugatti Chiron at full throttle could fully convert all the air in a one car garage into deadly exhaust in just 1.8 minutes. Don't worry though, at idle and in a much more pedestrian car, the air will last much longer. Just don't count on that saving you if you run your car in a closed garage. Safety first!