Cost of a Ruler
Date: 08/01/97 at 23:56:44 From: Anonymous Subject: Cost of a Ruler Dr. Math, I'm an elementary educator, and one of my parents (who happens to be an accountant) is trying to stump me. Can you please help me with this problem? Alice and Betty want to buy the same kind of ruler but Alice is 22 cents short and Betty is 3 cents short. When they combine their money, they still do not have enough money. What is the most the ruler could cost? Thank you for your help.
Date: 08/07/97 at 16:32:28 From: Doctor Rob Subject: Re: Cost of a Ruler Nice problem! Let A be the amount of money Alice has, and B the amount Betty has. Then the cost of the ruler is C = A + 22 = B + 3. This tells you that B = A + 19. When Alice and Betty put their money together, they have A + B = 2*A + 19 < C = A + 22, so A < 3 and B < 22. The cost of the ruler will be largest when A or B is largest. The largest amount of money Alice could have is 2 cents, and the largest Betty could have is 21 cents. The maximum cost of the ruler is then 2 + 24 = 21 + 3 = 24 cents. -Doctor Rob, The Math Forum Check out our web site! http://mathforum.org/dr.math/
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