I'm in a university probability class studying multivariate distributions and have a problem I'm stuck on.(adsbygoogle = window.adsbygoogle || []).push({});

Here goes:

In a clinical study of a new drug formulated to reduce the effects of arthritis, researchers found that the proportion p of patients who respond favourably to the drug is a random variable that varies from batch to batch of the drug. Assume that p has a probability density function given by

f(p)={12*(p^(2))*(1-p), whenever p is between 0 and 1 inclusive

{0, whenever p is elsewhere.

Suppose that n patients are injected with portions of the drug taken from the same batch. Let Y denote the number showing a favourable response.

(A) Find the unconditional probability distribution of Y for general n.

(B) Find E(Y) for n = 2.

I'm confused because there's no Y1 and Y2. Every problem I've done has Y1 and Y2. How do you find the unconditional probability distribution for just Y in this case? I would love any help. Just a suggestion needed.

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# Homework Help: Drug Probability Problem

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