The Student Room Group

probability question again

Given a standard shuffled deck of 52 cards, you flip through the deck starting at the top until you reach the first Ace (A). What position does that A need to be in to give an equal probability of running into another A or a 2 after that? (we have not specified whether you have already seen a 2, or not, prior to flipping the first A).
You have to find one and only one 2 before you find your first ace.

You cannot find anymore 2's or Aces before your first ace obviously. After the first ace has been found, this would leave 3 Aces and 3 2's, the probabilities are therefore equal, regardless of the amount of cards left. Therefore the ace could be in position 2 and in every position up until position 46, given those conditions are met.

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