Problem #92: A Weighty Problem I
A shopkeeper wants to be able to dispense sugar in whole pounds ranging from
one pound up to 40 pounds. He has a standard, equal-arm balance weigh scale.
Being of an extremely economical outlook, he wants to use the least possible
number of weights to enable him to weigh any number of pounds between 1 and 40.
How many weights does he need and what are they?