Beating the dealer with a strictly higher card
Question
You and a dealer are each dealt one card from the same shuffled -card deck. Card values run from two up to ace, suits are ignored, and ties go to the dealer. What is the chance that your card is strictly higher?
Short answer
. The two cards share a rank with probability . In the remaining of cases symmetry makes each player equally likely to hold the higher card, so you win with probability .
Adapted from Zhou, A Practical Guide to Quantitative Finance Interviews, sec. 4.1 Basic Probability Definitions and Set Operations, 'Card game (higher card)', p.60; question and answer rewritten by SelfMadeQuant.com.
See the hint and the full worked solution in the question bank (free account).
Open the worked solutionLessons behind this question
- Counting and Combinatorics
- Sample Spaces, Events, and the Probability Axioms
- Conditional Probability, Total Probability, and Bayes' Rule
Start with a free lesson: Probability Fundamentals is part of a free topic. Create a free account, no card needed, to read it in full with worked solutions.
Read it free