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Basic Probability, a la Shmoop. The Joker has heard about Two-Face's infamous

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coin flip... ...and has decided to incorporate a little

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chance into his criminal activity. He has the perfect plan - he'll use a deck

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of cards, and if he draws a spade - evil wins!

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However, the Joker is less than impressed with the destruction and chaos he has been

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causing since he switched to Geico... ...er... a system based on probability.

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For a super villain, being nice isn't exactly easy...

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...and the Joker has been losing a lot of sleep wondering where he went wrong.

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Two-Face has been getting all the headlines. What's a villain to do?

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The answer is to think about probability. Probability is the study of outcomes.

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For example, one outcome is that we'll go to Chipotle in the next two days.

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Another outcome is that we won't. However, given our penchant for eating burritos...

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...the probability may be higher than average for us here at Shmoop.

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But let's look at some real numbers. The most important equation in basic probability

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is: The number of favorable or wanted outcomes...

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...divided by... ...the number of outcomes that are possible.

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So, if we go back to our coin-flipping vs. deck of cards situation...

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...we can start to see where the Joker went wrong.

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When TwoFace flips a coin, he wants to get the side of the coin with the scratched head.

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So, that's "one" in the numerator. And with the coin, there are only two possible

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outcomes. The scratched side or the unscratched.

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We see that this means the probability is one over two that he will be evil...or 50%.

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However, for the Joker there are 13 spades in a deck, so we put 13 in the numerator.

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And there are 52 possible cards he might choose...so we put 52 in the denominator.

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Which means that the Joker only had a 25% chance of being villainous.

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No wonder TwoFace has been taking more candy from babies.

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Basic lesson for aspiring bad guys: Make sure you know your probability before

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deciding on some kind of flashy trick.

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