Good scales have equal arms (arms are the the things that connect the actual scale to the center), but in one grocery stall, the arms of the scale are not equal. Pending replacement, the manager wonders if he can give correct weight this way:
"I'll balance a 1-pound weight on the left with sugar on the right, and then I'll balance the 1-pound weight on the right with some more sugar on the left, and the sugar will add up to exactly 2 pounds."
Will it? What are other (assuming that the above works, it may not) ways of weighing 2 pounds of sugar, if you also have a lead shot with you to help weigh? (Note and hint: The lead shot has an unknown weight. You can make it whatever weight you choose. Remember, the arms aren't equal, and you need 2 pounds of sugar.)
Put two 1-pound weights on one side and an amount of sugar necessary to balance on the other side.
Then take of the weights. This side of the scale will now need two pounds to re-balance it.
If you only have a single weight you can either do this twice or create a one pound bag of sugar first and then use this bag and the weight to have a two pound total.
The lead shot has no important function. It could be used to save some sugar.
Posted by Jer
on 2004-05-24 09:28:23