Word Problem Hints
Date: 3/12/96 at 22:3:37 From: John Reichel Subject: help I have two questions I could use some help on. 1) There are 1000 lockers numbered 1 - 1000. Suppose you open all of the lockers, then close every other locker. Then, for every third locker, you close each opened locker and open each closed locker. You follow the same pattern for every fourth locker, every fifth locker, and so on up to every thousandth locker. Which locker doors will be open when the process is complete? 2) A certain substance doubles in volume every minute. At 9:00 a.m. a small amount is placed in a container and at 10:00 a.m. the container is just full. At what time was the container on quarter full? Could you please help me with these questions? I would greatly appreciate it. John Reichel
Date: 3/14/96 at 18:24:45 From: Doctor Jodi Subject: Re: help Hi John! Our office is overflowing with patients at the moment, so let me just try to put a bandaid on these problems for you... Thinking about the influence of FACTORS in the first problem might help. I imagine the row of lockers as a long line of off/on switches. Let me give you a hint on the second question. If the substance doubles every minute, when was the container half full? Can you use the same sort of approach to find out when it was a quarter full? I hope these ideas help you a bit; please write back and let us know how the problems are going, or to ask for more help when you need it. -Doctor Jodi, The Math Forum
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