Math, Revealed Test your knowledge of taxicab geometry, triangular numbers, the golden ratio and more. Credit... By Steven Strogatz * Published July 11, 2025 Updated July 12, 2025 “,” our four-part series exploring the mathematics behind everyday objects and experiences, recently came to a smashing conclusion. One installment took a spin through “,” a wacky but vital corner of mathematics in which circles aren’t round and pi equals 4. Another journey began with and led to Leonardo da Vinci, the golden ratio and ideal positioning of belly buttons. We had great fun on this adventure and hope to resume it before too long. In the meantime, here’s a quiz to test what you learned and your general math knowledge. Enjoy! Jens Mortensen for The New York Times 1. In , circles don’t look round — they form sharp, angular shapes. What shape do they resemble? Jens Mortensen for The New York Times 3. Mathematicians have long been fascinated by a special number that describes self-similar proportions. What is the approximate value of this ? Jens Mortensen for The New York Times 4. Leonardo da Vinci’s “Vitruvian Man” has been analyzed endlessly for hidden patterns. According to a 2015 study, does the navel divide the figure according to the ? 5. In the of soda cans standing on a flat surface, each can in the middle touches the same number of neighbors. How many is it? Jens Mortensen for The New York Times 6. In 2022, a mathematician won a Fields Medal for solving a problem about tightly in eight dimensions. Who did it? Jens Mortensen for The New York Times 7. The first four are 1, 3, 6 and 10. Why is 10 considered a triangular number? The New York Times, photo via Alamy 9. At a wedding reception, the bride seats eight of her ex-boyfriends together at a table. (This actually happened to me once.) If each ex-boyfriend shakes hands with each of the others, how many handshakes occur in total? Photo illustration by The New York Times, source photos by Balarama Heller for The New York Times 10. Four bugs start in the corners of a square that measures 1 foot by 1 foot. Each bug chases its clockwise neighbor, always crawling directly toward the neighbor’s current position. If they all crawl at the same speed, how far does each bug travel before they all meet at the center?

How Much of Our Math Series Did You Retain? Try This Quiz.

The article announces a math quiz testing knowledge of topics from a four-part series on mathematics, including taxicab geometry, triangular numbers, the golden ratio, and other mathematical concepts. The quiz features 10 questions designed to reinforce learning from the series.