Question

A drawer contains 10 blue pens. 10 black pens. and 10 red pens. Without looking

Mr. Lopez is going to take one pen from the drawer, use it, and then put it back into
me drawer. Then he is going to take another pen from the drawer to use. What is
the probability of Mr. Lopez taking a red pen first and then taking a blue pen?

Answer 1

5/12

Explanation:

Answer 2

Answer:1/3 chance of picking red first, 1/3 chance of blue second. Hence the chance of red then blue is 1/3.1/3 = 1/9.

Hope this helps.

Explanation: