Interesting Question 2

OK, here is an easy one:

There are m balls and n boxes.

Now a ball is randomly dropped into a box--the probability of a ball dropping into any box is equal;

Each box can contain at most c balls, meaning if more than c balls are dropped into the same box, then the extra balls will be discarded.

Also we know m > n, n * c > m, c < m

Question 1: Derive a relationship between the total number of balls (k) in all n boxes when all m balls are dropped and m;

Question 2: What is the expected number of empty boxes when all m balls are dropped.

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I got an answer for this one. It's great mental gymnastics, have fun!

Labels: Sexy Stats

posted by panda xuan @ 1:09 PM