(adsbygoogle = window.adsbygoogle || []).push({}); What is the probability that a number selected from 0-9 will be the same number as one randomly selected from 0-4?

Relevant equations: $$P(A \cap B) = P(A)*P(B|A)$$

I used the equation above, using A as the event that the number selected from 0-9 will be between 0 and 4, and B as the event that the two selections are the same. Putting these two together I got: $$P(A)*P(B|A) = \frac{5}{10}*\frac{1}{5}^2 = 1/50$$.

It seems alright but it feels too small of a chance for this to happen. I don't really understand probability theory that well. Any books to recommend?

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# Homework Help: Probability of 2 equivalent random selections from integer sets

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