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I've been asked to calculate the probability of winning
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The Mega Millions Jackpot
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So that's what I thought I'd do this video on.
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So the first thing is to make sure we understand what winning the jackpot actually means.
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So there are going to be two bins of balls.
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One of them is going to have 56 balls. So 56 balls in one bin.
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And then another bin will have 45 balls in it.
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So 46 balls in this bin right here.
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So they are going to pick 5 balls from this bin right here, and you have
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to get the exact number of these five balls. It can be in any order, so let me just draw
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So its one ball, all shaded so it looks like a ball.
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two balls, three balls, four balls
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and five balls
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And you just have to get the numbers in any order. And this is from the bin of 56
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From a bin of 56.
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And then you have to get the megaball right.
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and they're just going to pick one ball from there, which they call the megaball.
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They're going to pick one ball from there. And obviously this is going to be one of 46
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So, from a bin of 46.
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So to figure out the probability of winning is going to be one of all the possible
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all of the possibilites of the numbers you can pick
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Its essentially all the combination of the white balls times the 46 possibilites for the mega ball
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So, think about the combinations about the white balls
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There are couple ways you could do it
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if you are thinking in combinatorix terms
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it would essentially be like saying
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out of a set of 56 things, I am going to choose
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I'm going to choose 5 of them
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Literally, you could do this as
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56 choose 5
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Or, if you want to think of it in more conceptual terms
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the first ball I pick there is 56 possiblities
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Since we're not replacing the ball
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The next ball I pick
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There are going to be 55 posibilites
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the ball after that there is going to be 54 possibilities.
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The ball after that there will be 53 possibilities
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The ball after that there is going to be 52 possiblites.
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52, because I've already picked 4 balls
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Now this number right over hre
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when you multiply it out is the number of permutations
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if I cared about order
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If I got that exact combination
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But to win this, you don't have to write it down in the same order
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You just have to get those numbers in any order
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So what you want to do is want to divide this by the number of ways that five things can actually be
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ordered.
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And if you're ordering five things
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The first of the five things could take five different positions
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And the next one will have 4 positions left
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And the one after that will have 3 positions left
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and the one after that will have two positions
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And the fifth one will be completely determined because we've already placed the other four.
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So it will only have one position
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So when we calculate this part right over here
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This will tell us all of the combination of just the white balls
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So let's calculate that
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So just the white balls, we have 55
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sorry, 56 x 55 x 54 x 53 x 52
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and we're going to divide that
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by 5 x 4 x 3 x 2 x 1
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but we don't have to mutiply by one, but I'll do that just to show what we're doing
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And that gives us about 3.8 million
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So let me put that off screen, and let me write that number down
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So this comes out to 3 million 8 hundred and 19 thousand
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3,819,816
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So thats the number of possiblities here
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So just your odds of just picking the white balls right
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are one out of this
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assuming you only have one entry
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and then there are 46 possibilities for the orange balls
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so you're going to multiply that by 46
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And so that's going to get you
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So when you multiply it times 46
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Bring the calculator back
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so we're going to multiply our previous answer
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times 46
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Ans just means my previous answer
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Times 46, I get a little under 176 million
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A little under 176 million
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So that is, let me write that number
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So that gives us 175,711,536
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So your odds of winning it, with one entry
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because this is the number of possiblities
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And essentially for $1, you are getting one of those possibilities.
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Your odds of winning is going to be one over this
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And to put this into a little context
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I looked it up on the internet of what your odds are of actually getting struck by lightning in your
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lifetime
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And your odds of getting struck by lightning are 1 in 10,000
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1 in 10,000 chance of getting struck by lightning in your lifetime
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And we could roughly say that the odds of getting struck twice in your life time
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Or another way of saying it, the odds of you and your best friend
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both independently getting struck by lightning when you're not around eachother
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Is going to be 1 in 10,000 times 1 in 10,000
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and so that will get you 1 in - I have now eight zeros
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one, two, three, four, five, six, seven, eight.
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So that gives you one in one hundred million
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So you actually twice, almost this is very rough
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You're roughly twice as likely to get struck by lightning twice in your life
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than to win the MegaJackpot!