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What would the odds be to get 100% on a multiple choice exam where I guessed the answer to all 50 of the multiple choice questions (5 choices per questions)?

A 1 in how many chance?

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    $\begingroup$ "experimental mathematics" lol $\endgroup$ – Alex Mathers Jul 3 '15 at 19:35
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In every answer, you have $\frac15$ chance to guess the correct answer. You need that chance to occur all the $50$ time, and since all of your answers are independent events, you need to multiply these probabilties, therefore your chance: $(\frac{1}{5})^{50}=\frac{1}{5^{50}}$, which is not too big, you should learn for your exams. :)

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    $\begingroup$ I believe that you meant $(1/5)^{50}$, not $(1/50)^{50}$. $\endgroup$ – Mark Viola Jul 3 '15 at 19:50
  • $\begingroup$ Yes, thanks for correcting. $\endgroup$ – Atvin Jul 3 '15 at 20:49
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    $\begingroup$ You're welcome. My pleasure! And +1 for the answer $\endgroup$ – Mark Viola Jul 3 '15 at 21:06

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