Probability That The Second Marble Is Blue

If a blue marble was selected first there is now a 1 4 chance of getting a blue marble and a 3 4 chance of getting a red marble.

Probability that the second marble is blue. We can go one step further and see what happens when we pick a second marble. The probability is. And the probability that the third marble is white is 11 18 because we ve already chosen 2 marbles. So i got rd 1 4 and blue 1 7 so 1 4 1 7 1 28 but my choices are 1 8 b.

Find the probablity 1. For example a marble may be taken from a bag with 20 marbles and then a second marble is taken without replacing the first marble. If it is red it is placed back in the bag. What is the probability that the first marble was blue given the second marble chosen was also blue.

6 orange marbles 8 blue marbles and 6 white marbles. The sample space for the second event is then 19 marbles instead of 20 marbles. What is the probability of her passing the second test given that she has passed the first test. The probability of selecting a red marble on the first draw is 0 5.

A draw a tree diagram with probabilities to represent the sample space. The probability of the second marble being blue is 4 19 since we have 1 less marble but not 1 less blue marble. A box contains 8 blue pens 5 red pens and 7 black pens. There is a 2 5 chance of pulling out a blue marble and a 3 5 chance for red.

Dont get how knowing the second marble chosen helps me find the odds of the first marble being blue. This is called probability without replacement or dependent probability. If three pens are drawn at random from the box with replacement what is the probability that the first two pens are red and the third is black. The probability that the first marble is red is 5 20 or 1 4.

The probability is. 1 4 c 1 7 or d. 2 marbles are drawn without replacement from a box of 3 white 2 green 2 red and 1 blue marble. Two marbles are drawn without replacement.

2 7 so i am not sure what i am doing wrong. The probability of selecting a red marble and then a blue marble is 0 28. B find the probability that one orange marble and one blue marble are drawn in either order. A marble is chosen at random if the marble is blue or green it is set aside.

C find the probability that two white marbles are drawn.