MHB What Is the Probability of Drawing Specific Ball Colors from a Bag?

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The discussion revolves around calculating probabilities related to drawing balls from a bag containing 5 red, 4 blue, and 3 green balls. For part a, the probability of drawing two red balls, given that the first ball drawn is not replaced, is determined by the ratio of remaining red balls to total balls after the first draw. For part b, the focus is on the probability of drawing at least one green ball, which requires analyzing the scenario where the first ball is not green. The calculations involve understanding the total number of balls left after the first draw and the specific conditions set by the problem. The thread highlights the importance of conditional probability in these scenarios.
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Hi guys, I have a maths question about Probability, hope somebody can help me out, thank you very much.

There are 5 red, 4 blue and 3 green balls in a bag. Two balls are taken from the bag, one after the other. If the first ball is not replaced, and it was not green. What is the probability that:

a) both balls are red?
b) at least one ball is green?
 
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raindoe said:
Hi guys, I have a maths question about Probability, hope somebody can help me out, thank you very much.

There are 5 red, 4 blue and 3 green balls in a bag. Two balls are taken from the bag, one after the other. If the first ball is not replaced, and it was not green. What is the probability that:

a) both balls are red?
b) at least one ball is green?
a) There are a total of 12 balls in the bag, 3 of them red. What is the probability the ball drawn is red? If the first ball is red there are 11 balls left, 2 of them red. What is the probability the second ball is also red? So what is the probability they are both red?

b) You are told that the first ball drawn is "not green". "At least one ball is green" requires that the second ball also be green. There are 11 balls left. What is the probability the second ball is "green"?
 
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