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binomial distributions

A bag contains 4 red and 6 blue marbles. A marble is chosen at random, its colour noted and then returned to the bag. This procedure happens eleven times. what is the expected number of red marbles drawn?
Original post by raisaalom
A bag contains 4 red and 6 blue marbles. A marble is chosen at random, its colour noted and then returned to the bag. This procedure happens eleven times. what is the expected number of red marbles drawn?


The expected number would be the mean of the distribution.

I would first write down the model used for the distribution (i.e X ~ …). Then after defining the variables in the model used, how might you calculate the mean?
(edited 4 months ago)

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