AI InterviewSearch…Search problems, topics, or pages…Ctrl KGet started
Mediumcardsunion

~60s

A queen or a club

A card is drawn from a pack of 52. What is the probability that it is a queen or a club?

Show the answer and the worked solution

Correct answer: A.

4/13

Worked solution

  1. Favourable = 4 + 13 − 1 = 16 cards.
  2. Probability = 16/52 = 4/13.

Answer: 4/13.

The idea

P(A or B) = P(A) + P(B) − P(both). Forgetting the overlap gives 17/52, which is offered.

Shortcut. Take the 13 clubs and add only the 3 queens that are not clubs: 16/52 = 4/13. Adding the outside queens avoids the overlap by construction.

Common trap. "17/52" — adding 4 queens and 13 clubs without removing the queen of clubs, which is counted in both.

Probability

10 of 37

Level

Medium

Target time

~60s

A queen or a club — Probability Aptitude Question

A queen or a club: A card is drawn from a pack of 52. What is the probability that it is a queen or a club? Answer and worked solution on CodeKairo.

Question

A card is drawn from a pack of 52. What is the probability that it is a queen or a club?

Options

  1. 4/13
  2. 17/52
  3. 1/4
  4. 15/52
Show the answer and the worked solution

Correct answer: A. 4/13

Worked solution

  1. Favourable = 4 + 13 − 1 = 16 cards.
  2. Probability = 16/52 = 4/13.

Answer: 4/13.

The idea

P(A or B) = P(A) + P(B) − P(both). Forgetting the overlap gives 17/52, which is offered.

Shortcut. Take the 13 clubs and add only the 3 queens that are not clubs: 16/52 = 4/13. Adding the outside queens avoids the overlap by construction.

Common trap. "17/52" — adding 4 queens and 13 clubs without removing the queen of clubs, which is counted in both.

All Probability questions · placement mock tests