Blind card sorting puzzle – the answer

Here is another puzzle that I never got round to answering… Until today. Firstly, here is the puzzle again:

“A blind person is given a normal deck of 52 cards. They are told that exactly 10 of the cards are facing up, all the rest are facing down. How can the blind person divide the cards into 2 separate piles, with each pile consisting of an equal number of cards facing up?”

The answer is below

Take the top 10 cards of the deck and put them in a separate pile to the remaining 42 cards. Turn all of the 10 cards over. Now both piles will consist of an equal number of cards facing up.

If all of the 10 cards remove from the deck were originally face-up, turning them over will result in both piles containing 0 face-up cards. If none of the 10 cards remove from the deck were originally face-up, turning them over will result in both piles containing 10 face-up cards. The same is true if just some of the 10 cards remove from the deck were originally face-up… both piles will contain the same number of face-up cards

Advertisements

6 thoughts on “Blind card sorting puzzle – the answer

  1. I enjoyed this “10 cards riddle or puzzle.” Thought provoking questions I like to ponder and see. Keep up the great work on this blog, I love your background.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s