Abag contains 13 blue marbles and two white marbles of equal size a marble is randomly selected from the bag set aside and then a second marble is picked what is the probability that two white marbles are picked

Answer as a fraction is 1/105

Answer in decimal form is roughly 0.0095238

Explanation:

There are 13 blue marbles and 2 white. So there are 13+2 = 15 total.

The probability of picking a white marble is 2/15 as there are 2 white out of 15 total. Each marble is equally likely due to the equal sizes.

We do not put the marble back or replace it. This is from the phrasing "set aside", i.e. "no replacement". So there are 2-1 = 1 white left out of 15-1 = 14 total. The probability of picking a white marble again is 1/14

Multiply the two fractions:

(2/15)*(1/14) = (2*1)/(15*14) = 2/210 = 1/105 = 0.0095238