A player draws the cards from the a 52-card deck one by one, without putting them back in the deck.
Every time before drawing a card he guesses the suit of the card he will draw.
He decides to always guess the suit that occurs most frequently in the remaining deck (if there are
several such suits, he chooses any one of them).
Prove that he will guess the right suit at least 13
(In reply to re: simulation
by Ady TZIDON)
No need to guess at the average number of correct guesses if ignoring the number of cards remaining in each suit. In that case, the expected correct guesses are exactly 13. Calculated as expected 1/4 correct guesses per guess * 52.