Today, I have an interesting puzzle for you to solve involving a ‘khipu’, which was the Incan method of recording numbers with knots on a string. The Incans used khipus to keep track of dates, taxes, and measurements, but knowledge of how these numbers were represented was lost after the Spanish conquest. However, a high school math teacher in Brooklyn was able to decipher the system in 1912.
The puzzle involves looking at two sets of strings attached to a horizontal cord. Each set of four strings under the cord is linked by a single string above. By analyzing the knots on the strings, one can determine the three-digit numbers they represent. The ‘o’ knots encode the units digits, while the ‘x’ knots encode the tens and hundreds digits.
After carefully studying the patterns in the knots, you can figure out the numbers represented by each string. For example, in the first image, the strings represent 134, 366, 250, 055, and 805. The sum of the four bottom strings equals the number on the top string. This pattern holds true for the second set of strings as well, where the numbers add up to 658.
I hope you enjoyed this puzzle and challenge your problem-solving skills. If you want more puzzles like this, you can check out my book “The Language Lover’s Puzzle Book” or “Think Twice: Solve the Puzzles That (Almost) Everyone Gets Wrong”. Feel free to suggest any great puzzles for me to feature in the future by emailing me.
