>>30
(This is
>>28 and
>>33 speaking).
It's kind of funny you should take this precise example, because, as you should know, there is no such thing as a (non-compactly supported) measure on the set of non-negative integers, and hence you cannot really talk about the expected value of the random variable you consider here. Also, nobody calls that an "expectance".
But you do have a point: it is true that if you pick k people uniformly in a group of N, n of whom where glasses, the expected number of people wearing glasses among those you've picked is nk/N. So the *mean* probability of one people wearing glasses among those you picked, when averaged over *all* possible picks, is n/N. But that certainly was not the question (an expected value is not the same thing as a probability). It says nothing about what happens in any given group, so that, given no additional information, we simply tell. Probably
>>16's point.
Regarding my mathematical education, I can safely say it extends a bit further past whole numbers, although it revolves around them in some sense.