Pairs of cards are turned over: black pairs to the dealer, red pairs to you. What are your odds of ending ahead?

A dealer turns over a 52-card deck two cards at a time. Two blacks go to the dealer, two reds to you, and mixed pairs are thrown away. The story asks the probability you end with more cards. You type your answer and check it. Then you step through the answer and the breakdown.

Why quant interviews test this

It checks whether you write down the counts before quoting a probability. The written solution is at /brain-teasers/red-and-black-cards/solution.

The Red and Black Cards guide covers how scoring works, the strategy that wins, a worked example and the mistakes most players make.

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