SOLUTION: Suppose a multiple choice problem has n possible answers. You guess
an answer equally likely at random. If you get it wrong, you pick an
answer equally at random from the remaini
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Probability-and-statistics
-> SOLUTION: Suppose a multiple choice problem has n possible answers. You guess
an answer equally likely at random. If you get it wrong, you pick an
answer equally at random from the remaini
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Question 441696: Suppose a multiple choice problem has n possible answers. You guess
an answer equally likely at random. If you get it wrong, you pick an
answer equally at random from the remaining choices. You continue
until you have guessed the right answer, each time only guessing from
answers you have not tried yet.
(a) What is the expected number of guesses until you are correct?
You can put this solution on YOUR website! I won't solve the problem per se for you, because it involves tedious mathematical operating, but I'll tell you the plan of attack:
Let X = the random variable representing the number of guesses before you get the correct choice.
Then the pmf (which is a variant of the geometric distribution) is
The expectation is then
Good luck!
