这里有一些很不错的概率/逻辑题 http://excelexperts.com/Quant-Interview-Questions
例如:“You are given 3 chances to drop a non-biased dice (with number from 1-6). You can stop earlier, but the number of final drop is the money you can get. Give a strategy to maximize the money you can get.”
Answer:
on the third roll, your EV is 3.5, so on the second roll you'd want to stay on anything over 3.5, aka 4 5 or 6. so your EV for roll 2 is really [(3.5 + 3.5 + 3.5) + 4 + 5 + 6] = 25.5/6 = 4.25. Therefore, on roll 1, anything less than 4.25 wouldn't suffice. Thus, you'd only stay on 5 or 6.
The final EV is (4.25)x4 + 5 + 6, all divided by 6, or 28/6 = 4.666666666666666666