Question

You were trying to answer a multiple choice question on a standardized test there are six choices if you get the question are you game and play if you get a wrong you lose 1/3 point assume you can eliminate one of the six choices and you choose one of the remaining five at random as your answer what is the expected value of the number of points you get

Answer 1

Let's first calculate the probability of getting the question right if you eliminate one of the six choices. Since there are six options, initially you have a 1/6 chance of getting the question right. If you eliminate one of the options, you are left with five choices, so your probability of getting the question right increases to 1/5.

Now, let's calculate the expected value of the number of points you get. If you get the question right, you earn one point. If you get the question wrong, you lose 1/3 point. So, we can write the expected value as:

Expected value = Probability of getting the question right x Points for a correct answer + Probability of getting the question wrong x Points for a wrong answer

Let's plug in the values:

Expected value = (1/5) x 1 + (4/5) x (-1/3)

Expected value = 1/5 - 4/15

Expected value = -1/15

So, the expected value of the number of points you get is -1/15. This means that, on average, you can expect to lose about 0.067 points for each question you attempt.