Which is more likely, to throw at least 1 six with 6 dice, or at least 2 sixes with 12 dice, or at least 3 sixes with 18 dice?
Try it out and see what happens.
For the first one it is: \[ \binom{6}{1}\left(\frac{1}{6}\right)^1\left(\frac{5}{6}\right)^5 \]The second one is: \[ \binom{6}{2}\left(\frac{1}{6}\right)^2\left(\frac{5}{6}\right)^{10} \]The third one is: \[ \binom{6}{3}\left(\frac{1}{6}\right)^3\left(\frac{5}{6}\right)^{16} \]
I don't get it. How did you get this?
And I think you are wrong, first one equals about .4, second one equals about .067, last one equals about .006 . this is what I got on calculator. It doesn't make sense.
Oooh wait
Should be \[ \binom{12}{2} \]for the second and \[ \binom{18}{3} \]for the third...
Basically, the fraction parts are finding out the probability that the 6's come up consecutively at the start and then the rest are not 6's.
Then the binomials count how many ways you could shuffle the 6's around, so you account for every sequence they could appear in.
Hmmm, it's looking a lot like the binomial distribution but...
But it seems like it actually is the binomial distribution.
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