Brain Teasers & Mental Math
You roll a die. If even, you win that many dollars; if odd, you lose that many dollars. What is the expected value of the game?
Model answer
E = (1/6)(−1 −3 −5 + 2 + 4 + 6) = (1/6)(−9 + 12) = 3/6 = +$0.50. Positive…
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