If I know the probability of a lake being polluted is .14 and the probability of it being naturally polluted is .25, how do I find the probability that it is naturally polluted? I have played with this for a long time and still have no idea how to calculate it. In fact, I'm not even sure where to start. Any guidance would be greatly appreciated.(adsbygoogle = window.adsbygoogle || []).push({});

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# Homework Help: Probability question

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