face up, face down

February 27, 2012

Posed by Punit Rathore:

A blind man is handed a deck of 52 cards and told that exactly 10 of these cards are facing up. How can he divide the cards into two piles, not necessarily of equal size, with each pile having the same number of cards facing up?

Solution posted in comment 1.


A set of tennis

February 14, 2012

Djokovic beat Nadal 6-3 in a set. There were a total of 5 broken games in that set. Who served first in that set? (A broken game is one in which the server loses the game)