Problem 13
You are blindfolded and seated in front of a table
with a large number of pennies resting on it. Exactly
50 pennies are heads up, the rest have tails showing.
How can you divide all the pennies on the table into
two groups such that each group has the exact same
number of pennies heads up?
Note: There must be at least one penny in each
of the two groups (no empty groups allowed!). Also,
pennies may be moved around, turned over, or anything
you feel is necessary to complete the problem, but no
penny can leave the table.
