Question

A bag contains 6 red marbles, 3 blue marbles, and 7 green marbles. You choose one then a second without replacement. What is the probability that you draw 2 greens? (I know the answer is 0.175 but I don't know why)

Answer 1

So the number of green marble is 7.
The total amount of marbles are 16.

The probability of choosing a green marble is 7/16 on the first try.

Now without replacement, we have a total amount of 6 green marbles and 15 total marbles, altogether.

So the probability of choosing a green for the second time, without replacement is 6/15.

To find both the probabilities combined, multiply them together:

This would be 7/16 * 6/15.

This would result in 0.175 in the calculator.


Hope this helps. If you have any questions, place it in the comment section below.