Question

there are 3 white marbles and 7 blue marbles in a bag. Jamie will randomly pick two marbles out of the bag without replacing the first marble chosen. What is the probability of Jamie picking two blue marbles ?

Answer 1

Hello!

Right now there are ten total marbles in the bag. Our first probability is seen below.

$\frac{blue}{total} = \frac{7}{10}$

If she were to select a blue marble without replacing it, there would only be nine marbles left. There would also only be 6 blue marbles left.

$\frac{blue}{total} = \frac{6}{9}$

Now we will multiply our two probabilities.

$\frac{7}{10} (\frac{6}{9})= \frac{42}{90} = \frac{7}{15}$

Therefore the probability of this event is 7/15, or about 46.67%.

I hope this helps!