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>> Imagine that we roll a fair, six‐sided die 1000 times. Out of 1000 rolls, how many times do you think the die would come up as an even number?

A classic example of a question you can only answer if you don't know what you're talking about. I bet they think the answer is 500.

500 is the most likely result, but the odds of actually getting 500 heads on 1000 flips of a fair coin are 2.5%, 1 in 40. A little ways out, at 505 (or 495) heads, the odds have fallen all the way to... 2.4%.

This is kind of like asking "Imagine that we roll a fair, six-sided die one time. Out of that one roll, which number do you think would come up?"

Except, assuming you make the best possible guess both times, you're more than six times as likely to be right for my revised question.



Isn't the correct answer about 500? Sure, getting exactly 500 would not be highly probable. But getting approximately 500 would be.


Is "approximately 3.5" the answer to "which number will come up when I roll this 6-sided die once?"?


The Expected value would be exactly 3.5 ( https://en.wikipedia.org/wiki/Expected_value#Finite_case ). But isn't the question malformed since for a single role only one of the discrete values can come up?


How is "which number will come up when I roll this die?" better or worse posed than "how many even numbers will come up when I roll this die several times?"?




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