Question

A card is chosen randomly from a pack of playing cards. The probability that it is a black king or queen of heart or jack is

• A. 1/52
• B. 6/52
• C. 7/52
• D. None of these

Answer 1

Answer: (C)

7/52

Answer 2

Let A, B, C are the events of choosing a black king, a queen of heart and a jack respectively.

\ $P ( A ) = \frac { 2 } { 52 } , P ( B ) = \frac { 1 } { 52 } , P ( C ) = \frac { 4 } { 52 }$

These are mutually exclusive events,

\ $P ( A \cup B \cup C ) = \frac { 2 } { 52 } + \frac { 1 } { 52 } + \frac { 4 } { 52 } = \frac { 7 } { 52 }$.