SOLUTION: . In a multiple-choice test, each question has four options. Students will get 2 points for each correct answer; lose 1 point for each incorrect answer; and receive no points for u
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-> SOLUTION: . In a multiple-choice test, each question has four options. Students will get 2 points for each correct answer; lose 1 point for each incorrect answer; and receive no points for u
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Question 380302: . In a multiple-choice test, each question has four options. Students will get 2 points for each correct answer; lose 1 point for each incorrect answer; and receive no points for unanswered questions. A student does not know the correct answer for one question. Is it to her advantage or disadvantage to guess an answer? Show your calculations for expected value. Show your work for full credit.
You can put this solution on YOUR website! There is a 1/4 chance of obtaining the right answer, and a 3/4 answer of obtaining the wrong answer (provided he answers). Thus the expected value is
(1/4)(2) + (3/4)(-1) = -1/4.
This is less than 0, so it would be disadvantageous to guess.
