Twenty-one persons sat down to dinner at an inn, with the landlord at
the head of the table. When dinner was finished it was resolved that one
of the number should pay the whole score; to be decided as follows. A
person should commence counting the company, and every seventh man was
to rise from his seat, until all were counted out but one, who was to be
the individual who should pay the whole bill. One of the waiters was
fixed upon to count the company out, who, owing his master a grudge,
resolved to make him the person who should have to pay. How must he
proceed to accomplish this?
_Explanation._—Commence with the sixth from the landlord. You illustrate
with counters.