Question

A card is drawn at random from a well-shuffled deck of playing cards. Find the probability that the card is drawn is a king or a jack.

Answer 1

Step 1 Determining the probability:

We know that a deck has $52$ cards.

So, the total number of outcomes $=52$.

A deck of cards has are $4$ king and $4$ jack cards.

So, the total number of favorable outcomes

$$\begin{gathered} =Kingcards+Jackcards \\ =4+4 \\ =8 \end{gathered}$$

The formula for probability is

$$\begin{gathered} Probabilty=\frac{Numberoffavorableoutcomes}{Totalnumberofoutcomes} \\ \Rightarrow P\left(akingorajack\right)=\frac{8}{52} \\ \therefore P\left(akingorajack\right)=\frac{2}{13} \end{gathered}$$

Hence, the probability of picking a king or a jack card is $\frac{2}{13}$.