Enigma 1354: Sound idea
20 January 2014
Posted by on
From New Scientist #2513, 20th August 2005
Joe’s daughter has been asking him for weeks to make a wind chime. So this week Joe cut a length of stainless steel tubing into 10 lengths from 1 cm to 10 cm in steps of 1 cm. He also cut out a disc from a sheet of stainless steel and drilled 10 evenly spaced holes round the perimeter and one in the centre.
Joe hung one tube from each hole and hung the disc up by a thread from its centre. That was a big mistake as the disc tilted right over.
So Joe rearranged the tubes until the disc balanced perfectly. In making a note of the lengths of the tubes in order round the disc the result was an 11-digit number.
What is the smallest of all the 11-digit numbers Joe could have written down?