1100.71 – Martha the Grocer and her Two-Pan Scale

Tags:Problem Set 9GeometryArithmetic: Z

Martha has a 2-pan scale and a set of 4 shiny brass weights. She claims that she can weigh out any whole number of ounces up to and including 40 using just these weights. And she’s right! What is the weight of each of her 4 weights? (Note that you can put weights on either pan of the scale. thus either addition or subtraction of the weights is possible.)


Solution. The weights are 1, 3, 9 and 27 ounces. (Powers of 3. Hmmm)