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Did the brainy droid C-3PO get the calculation right? Are the odds really 3,720 to 1? Those are exactly the questions we'll be answering today.

Star Wars Math
In case you haven't seen The Empire Strikes Back (the second film in the original Star Wars trilogy) in a while, (or if, heaven forbid, you've never seen it!), let me remind you of the part in question. It's when Han Solo and the gang decide to take their chances and evade the enemy in an asteroid field.

Upon making this bold and perhaps reckless decision, the ever-attempting-to-be-helpful droid C-3PO tells Han: "

Sir, the possibility of successfully navigating an asteroid field is approximately 3,720 to 1."

Han being Han, of course, replies: "Never tell me the odds."

Does C-3PO know what he's talking about? Or is he just a "bucket of bolts," so to speak? To figure that out, we first need to understand what odds are. So, without further ado…

What Are Odds?
When we first talked about odds and probabilities, we learned that probability is a number between 0 and 1 that tells you the likelihood that something will happen. In particular, a probability of 0 means there’s literally no chance of that thing happening, a probability of 1 means that it’s certain to happen, and a probability in between these extremes such as 0.5 means there's a 50% chance of it happening.

Odds, on the other hand, are kind of (pardon the pun) odd because they tell you essentially the same thing as probabilities but in a rather funny and somewhat convoluted way.

The most common way to write odds is what’s called “bookmakers odds.” For example, 3-1 (pronounced “three to one”) odds of a horse winning a race means that for every four races (the total of the two numbers in 3-1), the horse will lose three times and win once. In other words, the first number is the number of ways or times that something (in this case the horse winning) won't happen and the second is the number of times it will—at least according to the odds.