Saturday, April 22, 2017

Marking a Ruler

A 13-inch ruler only needs four markings on it so that it can be used to measure any whole number of inches from 1 to 13. At what positions should the four markings be? (Do not include the two ends, which are understood to be markings 0 and 13.) Click below to see the answer.

1 comment:

Trevel said...

Interesting: I found two other solutions, and I am willing to claim that that is all that there is (beyond the mirror of each, so I suppose 6 total.)

Would post here but spoilers.