# On a 50 question multiple choice exam with 5 choices per questions, What are the odds that I get 100% if I were to Guess every answer? [closed]

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?

## closed as off-topic by George V. Williams, Mike Pierce, Paramanand Singh, user223391, Jonas MeyerJul 4 '15 at 7:00

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• "experimental mathematics" lol – Alex Mathers Jul 3 '15 at 19:35

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. :)
• I believe that you meant $(1/5)^{50}$, not $(1/50)^{50}$. – Mark Viola Jul 3 '15 at 19:50