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Best Guess · Puzzle #36 · Wednesday, November 4

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. On average, how many miles did each licensed US driver drive in 2024?

    The answer: about 13,700 miles. The US reached a record 240 million licensed drivers in 2024.

    Napkin math
    1. 35miles a day
    2. ×365days a year

    ≈12.8kmiles

    The real answer is about 13,700 miles (Federal Highway Administration). On a napkin, take 35 miles a day, times 365 days a year, and you get about 13,000 miles. It's 1.1 times too low, which as a guess would still have scored 9.7 out of 10. Because only the ratio counts, anything between 6,900 miles and 27,000 miles was worth 7.0 or more.

    Source: Federal Highway Administration, Our Nation's Highways 2026 - Drivers

  2. 2. How many US adults watched the August 2017 total solar eclipse, in person or on a screen?

    The answer: about 215 million. 154 million watched it directly, through eclipse glasses or pinhole viewers, and 61 million on a screen.

    Napkin math
    1. 250Madults in the US
    2. ×3adults watching out of
    3. ÷4adults

    ≈188Madults

    The true figure is about 215 million adults (University of Michigan). To reason it out, take 250 million adults in the US, times 3 adults watching out of every 4 adults, and you get about 190 million adults. The estimate is 1.1 times too low, close enough to score 9.4 out of 10. Any guess from 110 million adults to 430 million adults scores 7.0 or better, because the game only counts how many times off you are.

    Source: University of Michigan (via Futurity), 215 million U.S. adults watched the solar eclipse

  3. 3. How many McDonald's restaurants were there worldwide at the end of 2025?

    The answer: 45,356. Only 13,706 were in the US, and about 95% of all McDonald's restaurants are run by franchisees.

    Napkin math
    1. 330Mpeople in the US
    2. ÷25kpeople to a McDonald's
    3. ×3times over, for the rest of the world

    ≈39.6krestaurants

    The real answer is 45,356 restaurants (McDonald's Corporation, as of December 31, 2025). Without looking anything up, take 330 million people in the US, divided by 25,000 people to a McDonald's, times 3 times over, for the rest of the world, and you get about 40,000 restaurants. It's 1.1 times too low, which as a guess would still have scored 9.4 out of 10. Any guess from 23,000 restaurants to 91,000 restaurants scores 7.0 or better, because the game only counts how many times off you are.

    Source: McDonald's Corporation, Form 10-K for fiscal year 2025

  4. 4. How many people in the US watch birds?

    The answer: about 96 million. 95% of them, about 91 million people, watch from around their own homes.

    Napkin math
    1. 330Mpeople in the US
    2. ÷3people per birdwatcher (about 1 in 3)

    ≈110Mpeople

    The real answer is about 96 million people (US Fish and Wildlife Service, as of 2022). On a napkin, take 330 million people in the US, divided by 3 people per birdwatcher (about 1 in 3), and you get about 110 million people. It's 1.1 times too high, which as a guess would still have scored 9.4 out of 10. The target is wider than it looks: every guess between 48 million people and 190 million people scores at least 7.0.

    Source: US Fish and Wildlife Service, Birdwatching in America

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