Minus' Solution to

Posted April 1 - 7, 1996

Quinton turns over both the hourglasses. When the 8 minute hour-glass runs out, Quinton immediately turns the left handle and simultaneously turns over the 13-minute hourglass (which now has 5 minutes of sand in it). When this 5 minutes of sand runs out, he turns the 13-minute hourglass over again. Once the sand runs out, 18 minutes should have elapsed and Quinton immediately turns the right handle.

What does he find? Who knows -- maybe no more than there was in Al Capone's safe!

Your Solutions

Our best solution this week came from John Moser (johnmoser@msn.com). He suggests that Quinton...

Start the two hourglasses together. When the 8 minute one empties turn the left handle (and turn the 13 minute hourglass over). Turn the 13 minute one when it empties. When this one empties the second time turn the right handle. Enjoy your prize but watch for booby traps.

REASON---- 13 - 8 = 5 minutes plus 13 more minutes = 18 minutes plus turning time (that's why you need to turn as few times as possible)