In the question I am working on, there are three jars filled with balls, and a die. Depending on the number that comes up from the die determines which jar a ball is drawn from. I created a tree and have all my individual probabilities.
The question asks the probability of a certain color ball and doesn't give a specific jar. I took all the probabilities for each jar for the particular color and added them up. Is this the correct way to do it. I can't see multiplication beause one jar doesn't have this particular color ball and multiplication would give your final answer of zero.
Another question asks the probability of a certain color ball being picked that doesn't come from a certain jar.
For this I am thinking 1-P(of jar not included) multiplied by the P(of other two jars), but this too would lead to a zero.