Suppose boxes of cereal are filled with a random prize, each drawn independently and uniformly from 6 possible prizes. If N boxes of cereal is bought, what is the expected number of distinct prizes that will be collected?
Hint: Use indicator random variables.
Comments: The question being asked is worded a bit strange. My initial thought was to find N, but with the helpful hints below, I now understand what the question is asking (Thank you all).