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.
- Topic: Probability
- Section: Quantitative Aptitude
- Difficulty: Medium
- Time target: 60 seconds
Question
A card is drawn from a pack of 52. What is the probability that it is a queen or a club?
Options
- 4/13
- 17/52
- 1/4
- 15/52
Show the answer and the worked solution
Correct answer: A. 4/13
Worked solution
- Favourable = 4 + 13 − 1 = 16 cards.
- 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.