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Best Guess · Puzzle #39 · Saturday, November 7

Best Guess: the answers

Four questions, each with one true number. Here they are with their answers, how to reason each one out, and where the number comes from. Play today's Best Guess.

  1. 1. How many people in the US had a job in September 2026?

    The answer: about 163 million. That's the seasonally adjusted count of employed people from BLS's monthly household survey.

    Napkin math
    1. 330Mpeople in the US
    2. ×0.8of them are adults
    3. ×0.6of adults have a job

    ≈158Mpeople

    The answer comes to about 163 million people (US Bureau of Labor Statistics). On a napkin, take 330 million people in the US, times 0.8 of them are adults, times 0.6 of adults have a job, and you get about 160 million people. That lands all but on the answer, worth 9.9 out of 10 as a guess. Any guess from 82 million people to 330 million people scores 7.0 or better, because the game only counts how many times off you are.

    Source: US Bureau of Labor Statistics, The Employment Situation, Table A-1: Employment status of the civilian population by sex and age

  2. 2. How many miles did Charles Lindbergh fly on his 1927 nonstop solo flight from New York to Paris?

    The answer: 3,610 miles. The flight took 33 hours, 30 minutes, and a crowd of 100,000 greeted him at Le Bourget Field.

    Napkin math
    1. 7hours for a jet from New York to Paris
    2. ×500miles an hour

    ≈3,500miles

    The answer comes to 3,610 miles (Smithsonian National Air and Space Museum). To reason it out, take 7 hours for a jet from New York to Paris, times 500 miles an hour, and you get about 3,500 miles. That lands all but on the answer, worth 9.9 out of 10 as a guess. Any guess from 1,800 miles to 7,200 miles scores 7.0 or better, because the game only counts how many times off you are.

    Source: Smithsonian National Air and Space Museum, Ryan NYP "Spirit of St. Louis"

  3. 3. How fast does sound travel through air at sea level on a standard day, in miles per hour?

    The answer: about 761 mph. That's about 1,100 feet per second, which is why counting the seconds between flash and thunder tells you how far away lightning struck.

    Napkin math
    1. 3,600seconds an hour
    2. ÷5seconds for thunder to travel a mile

    ≈720miles per hour

    The true figure is about 761 mph (NASA Glenn Research Center). On a napkin, take 3,600 seconds an hour, divided by 5 seconds for thunder to travel a mile, and you get about 720 miles per hour. It's 1.1 times too low, which as a guess would still have scored 9.8 out of 10. Because only the ratio counts, anything between 380 miles per hour and 1,500 miles per hour was worth 7.0 or more.

    Source: NASA Glenn Research Center, Beginner's Guide to Aeronautics: Speed of Sound

  4. 4. How many miles of steel wire are in the Golden Gate Bridge's two main cables, combined?

    The answer: 80,000 miles. Each main cable holds 27,572 separate galvanized steel wires, each 0.192 inches across.

    Napkin math: Each main cable is a bundle of tens of thousands of pencil-thin wires, and each wire runs well over a mile from anchorage to anchorage, so multiply tens of thousands of wires by about 1.5 miles.

    The true figure is 80,000 miles (Golden Gate Bridge, Highway and Transportation District). With no neat arithmetic to lean on, start with the order of magnitude: this one is in the tens of thousands. The target is wider than it looks: every guess between 40,000 miles and 160,000 miles scores at least 7.0.

    Source: Golden Gate Bridge, Highway and Transportation District, Design & Construction Stats

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