When do more cars travel on the highway, before or during rush hour?  It’s rush hour, right? Well, it depends on how you interpret the question. During rush hour, plenty of cars flood the highway at once, but they all take more time to get where they’re going. In fact, there’s a good chance that many people sitting in traffic will be late. Before rush hour, however, the highway traffic is somewhat below capacity, but the highway actually allows more people to get to where they’re going on time.

Say someone places a counter at one mile marker, then another counter several miles down the road. In the middle of the day--say, between 2 and 3 p.m.--the counter would tick off plenty of cars. But between 5 and 6 p.m. the counters would actually tick off fewer cars, because of course all the cars would be slowly inching forward. So now imagine two scenarios: a horrific, 24- hour rush hour, and another where highway traffic is at three-quarters capacity. Which scenario would involve more cars? The answer is three-quarters capacity.

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