What is the probability of drawing a King or a Queen or a Jack from a deck of cards ?

Explanation

Number of cards n(S) = 52
No. of King cards n(A) = 4
No. of Queen cards n(B) = 4
No. of Jack cards n(C) = 4
Probability of drawing a King card
` = (n(A))/(n(S)) = (4)/(52)`
Probability of drawing a Queen card
`= (n(B))/(n(S)) = (4)/(52)`
Probability of drawing a Jack card
` = (n(C))/(n(S)) = (4)/(52)`
`:.` The Probability of drawing a King or a Queen or a Jack from a deck of cards
`= P(A) + P(B) +P(C) = (4)/(52)+(4)/(52)+(4)/(52)=(4+4+4)/(52)=(12)/(52)=(3)/(13)`