How many marbles are in the bag of blue and red?

There is a bag filled with 4 blue and 5 red marbles. A marble is taken at random from the bag, the colour is noted and then it is replaced. Another marble is taken at random. What is the probability of getting 2 reds?

What are the odds of getting a red marble?

We can go one step further and see what happens when we pick a second marble: 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. If a red marble was selected first there is now a 2/4 chance of getting a blue marble and a 2/4 chance of getting a red marble.

What is the probability of getting two red balls in blackjack?

The probability of getting a red ball on the first draw is 6/13. Given replacement, the probability of getting a red ball on the second draw is also 6/13. The probability of getting two red balls is 6/13*6/13 or 36/169. 8 clever moves when you have $1,000 in the bank.

What is the chance of two blue marbles being 7/17?

Since you have two blue marbles, this means it is without replacement (with replacement gives a different answer). To start off with, 7/17 are blue. With one less marble and one less blue, the chance for the second is 6/16, so multiplying these together, 7/17 * 6/16 = 21/136. Comment on David Severin’s post “Since you have two blue m…”

What is the probability of selecting 2 red marbles from the bag?

The probability of selecting 2 red marbles from the bag, consecutively and with replacement, is 31\%. There is a bag filled with 5 blue and 6 red marbles. A marble is taken at random from the bag, the colour is noted and then it is replaced. Another marble is taken at random.

What happens when a marble is taken at random?

A marble is taken at random from the bag, the colour is noted and then it is not replaced. Another marble is taken at random. What is the probability of getting 2 of the same colour?

What are the odds of getting a blue marble?

For each draw, the chances of getting a blue marble are 3 of 7; the chances of getting a red are 4 of 7. The chances of drawing a blue on both draws is (3/7)^2 or 9/49, and the chances of getting red on both draws is (4/7)^2 or 16/49.