Card Face Puzzle

42.2K Views

A pack of cards has 40 cards. You are blindfolded. Out of 40, 25 cards are facing down while 15 are facing up. You have been asked to divide this pack of cards into two decks – so that each deck contains an equal number of face-up cards. Remember, you are blindfolded.

How will you do it?

Share
Add Comment

  • 1 Answer(s)

    Split the pack to two parts of 25 and 15 cards. Now, consider the 15-card deck. Let there be ‘X’ face-up cards in this set (‘X’ may be 0 – 15).  Since total number of face-up cards in the pack is 15,  out of which ‘X’ are in now the 15-card deck,  the other deck (of 25) will have the remaining (15 – X) face-up cards. Now, I flip ALL cards in the 15-card deck. Since there were ‘X’ cards face-up earlier, now I have those X cards face-down and remaining (15 – X) cards face-up, which is equal to the No. of face-up cards in the other  deck. Solved.

    Viji_Pinarayi Expert Answered on 5th December 2023.
    Add Comment
  • Your Answer

    By posting your answer, you agree to the privacy policy and terms of service.
  • More puzzles to try-