(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

There are 50 balls in a bag, all are the same except for the color. 4 of them are white while the rest (46) of them are red. Now randomly draw balls from the bag, one at a time, without replacement. What is the expected number of red balls that you will draw before you first draw a white ball?

2. Relevant equations

If a discrete random variable X takes only positive values, then its expectation

[tex]E(X) = \sum_{k=1}^{+\infty}P(X \geq k)[/tex]

3. The attempt at a solution

Let X be the number of red balls drawn before first drawing a white ball. I can't seem to find [tex]P(X \geq k)[/tex]. Can somebody give me a hint?

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# Homework Help: Expected number of red balls drawn before drawing a white ball

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