Question

There are 2 black pens and 4 blue pens in a drawer. Lisa randomly takes out a black pen and puts it back. Without looking, she pulls out another pen.

Are these events dependent or independent?

Answer 1

independent?

Answer 2

Correct. By putting the first pen back in the drawer, the second time she draws a pen is exactly the same as the first time she draws a pen. The outcome of the first drawing does not affect the outcome of the second drawing. This is why the events are independent.