# Question: some number of pennies are spread on a table they...

###### Question details

Some number of pennies are spread on a table. They lie either heads up or tails up. Unfortunately, you are blindfolded and thus both the coins and the table upon which they sit are hidden from view. You can feel your way across the table and thus can count the total number of pennies on the table's surface, but you cannot determine if any individual penny rests heads up or down (perhaps you're wearing gloves). You are informed of one fact (beyond the total number of pennies on the table): Someone tells you the number of pennies lying heads up. While remaining blindfolded, you may now rearrange the coins, turn any of them over, and move them in any way you wish as long as the final configuration has all the pennies resting (heads or tails up) on the table. Your challenge is to arrange the pennies into two collections and then turn over whatever pennies you wish so that both collections have the same number of heads-up pennies.