# A card is drawn from a standard deck. A second card is drawn, without replacing the first card. Consider the following events: Event A = The first card selected is red. Event B = The second card selected is black. What word describes the relationship between events A and B?

Jan 31, 2015

They are not independant.

Event A has a chance of $\frac{26}{52} = \frac{1}{2} = 0.50$ of happening

Now that you have removed this card from the deck, the chance of the second card being black is not 50/50 anymore, but:

$\frac{26}{51} \approx 0.51$ (second card red would be $\frac{25}{51} \approx 0.49$)

In this case the draw (without putting back) influences the second draw.

If you put back the card after each draw, the events would be independant, for every time you draw a new card, the chances would be 50/50.