An urn contains 10 bails: 5 are white, 3 are red, and 2 are black. three balls are drawn at random, with replacement, from the urn. what is the probability that all 3 balls are different colors?

If three balls are drawn from 10 balls with replacment, then you should count:
1. the probability to choose white ball - ;
2. the probability to choose red ball - ;
3. the probability to choose black ball - .
Using the product rule you can conclude that the probability that all 3 balls are different colors is:

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Ibelieve the answer is b. y=0 would make the line horizontal across the x.