Here’s a puzzle a co-worker shared with me recently. See how you do with it!
Suppose you have five bags of gold coins. All of the coins weigh exactly 1 lb each except for all of the coins in one bag whose coins weigh 1 lb 1 oz each. The bags are unmarked, and there is no visible indication as to which bag holds which coins. The bags may contain different quantities of coins.
Suppose you have a scale on which you can make exactly one instantaneous measurement – put something on the scale, push the “Weigh” button, and you get a reading of the weight at the moment the button is pushed.
Using the scale, is it possible to identify which of the 5 bags contains the heavier coins with only a single measurement? If so, how?
[spoiler /Show Answer/ /Hide Answer/]On the scale, place one coin from the first bag, two coins from the second bag, three coins from the third bag, four coins from the fourth bag, and five coins from the fifth bag. When the weight is taken, the number of ounces will indicate which bag has the heavier coins. That is, if the weight is 15 lb 3 oz, then the third bag has the heavier coins.[/spoiler]
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ePeterso2
Who I Am
ePeterso2I’m Eric Peterson, and my email address is epeterso2@puzzlehead.org.
I’m a software engineer who lives in a suburb of Fort Lauderdale, Florida. I’ve enjoyed solving puzzles for years, and a few years ago I began constructing puzzles of my own.
If you’re ever in Broward County and would like to get together some time, please send me a note by email and let me know. I love the opportunity to meet with other puzzleheads, especially if it involves lunch.
Puzzle Testing
I believe that the best way to make a puzzle even better is to ask someone else to solve it. You learn so much about how people think, how people approach your puzzle, pitfalls they may encounter, and outright errors in your construction by having someone else try it before you unleash it upon the world.
If you’re a puzzle constructor, I would be honored to test your puzzle for you. Send me email with your puzzle or a link to it, and I’ll try solving it, as long as I have time available to do so. I’m a busy guy, so my time is limited … but I’m always open to a challenge.
My Public Profiles
* My Linked In profile
* My Geocaching.com profile
* My FloridaCaching.com profile
Puzzles I’ve Written
* Geocaching puzzles
Puzzles I’ve Solved
* Geocaching puzzles (solved and found)
What Happened to ePeterso1?
ePeterso1 was a horrible experiment gone wrong that had to be hunted down and killed before he claimed the lives of any more innocent victims. Most of the bugs that caused ePeterso1 to go haywire have been corectted in ePeterso2.
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