Ms. Haden has the following pens in her desk drawer.
2 red pens
3 blue pens
4 black pens
Ms. Haden will randomly select one pen, keep it, and then randomly select another pen. What is the probability that Ms. Haden will select a blue pen first and then a black pen?
There are 2+3+4=9 total pens. The chance of selecting a blue pen is 3/9, or 1/3. Then there's 8 pens left, so the chance of selecting a black pen is 4/8=1/2. To answer the question, we multiply 1/3*1/2=1/6.
