Question

A card is drwan from a well shuffuled pack of 52 playing card. What is the probability that the card drawn is either a red or king

Answer 1

Given
n(s) =52
Let be the event A of getting a red card

red card =13
n(A) =13

P(A) =n(A) /n(s)
=13/52


Let be the event B of getting a king

King card=4
n(B) =4

P(B) =n(B) /n(S)

=4/52

Both are not mutually exist

AnB=a king card

n(AnB)=1

P(AnB) =n(AnB) /n(S)
=1/52

Using addition theorem,

P(AuB) =P(A) +P(B) -P(AnB)
=13/52+4/52-1/52
=13+4-1/52
=17-1/52
=16/52
P(AuB) =4/13

Answer 2

P(either red or king)=28/52=7/13