Probability Marbles Without Replacement Khan Academy

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Probability marbles without replacement khan academy. You see them there. So the probability of getting 2 blue marbles is. If the first pick is green then you don t have 3 green marbles in a bag of 5. If the first pick is green you now have 2 green marbles in a.

We could also do that with rolling a die. One two three four five and six. So that s my bag and we re going to assume that it s a transparent bag so it looks like a vase. So we have a bag with 9 red marbles 2 blue marbles and 3 green marbles in it.

If we replace the marbles in the bag each time then the chances do not change and the events are independent. What is the probability of randomly selecting a non blue marble from of the bag. So they say the probability i ll just say p for probability. Let me make this clear not independent.

If one of these was you can t have a 60 probability of getting a heads and then a 60 probability of getting a tails as well. The events are independent the chances don t change without replacement. But we have 9 red marbles so let me draw 9 red marbles. Or in particular the second pick is dependent on the first.

A fair six sided die is going to have six possible outcomes. Let s get you started with a great explanation of dependent probability using a scenario involving a casino game. Dependent on the first pick. Find the probability of pulling a yellow marble from a bag with 3 yellow 2 red 2 green and 1 blue i m assuming marbles.

You have a 1 2 probability. So there s not any replacement here. So let s draw this bag here. They have to add to 1.

Because then you would have essentially 120 probability of either of the outcomes happening which makes no sense at all. The probability of picking a yellow marble. And we write it as. So these are not independent events.