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Best Guess · Puzzle #27 · Monday, October 26

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 licensed drivers were there in the US in 2024?

    The answer: about 240 million. The count includes restricted licenses and graduated licenses held by teens.

    Napkin math
    1. 330Mpeople in the US
    2. ×0.75of them have a driver's license (3 in 4)

    ≈248Mlicensed drivers

    The true figure is about 240 million licensed drivers (Federal Highway Administration). On a napkin, take 330 million people in the US, times 0.75 of them have a driver's license (3 in 4), and you get about 250 million licensed drivers. That is almost exactly the real number, and a guess like it scores 9.9 out of 10. Any guess from 120 million licensed drivers to 480 million licensed drivers scores 7.0 or better, because the game only counts how many times off you are.

    Source: Federal Highway Administration, Highway Statistics 2024, Table DL-22: Total Licensed Drivers: Distribution by Age Group 2024

  2. 2. How many Starbucks stores were there worldwide at the end of fiscal 2025?

    The answer: 40,990. The total fell by 107 in the final quarter after 627 stores closed under the company's restructuring plan.

    Napkin math
    1. 330Mpeople in the US
    2. ÷20kpeople to a Starbucks
    3. ×2times over, for the rest of the world

    ≈33kstores

    The answer comes to 40,990 stores (Starbucks Corporation). To reason it out, take 330 million people in the US, divided by 20,000 people to a Starbucks, times 2 times over, for the rest of the world, and you get about 33,000 stores. It's 1.2 times too low, which as a guess would still have scored 9.1 out of 10. Any guess from 20,000 stores to 82,000 stores scores 7.0 or better, because the game only counts how many times off you are.

    Source: Starbucks Corporation, Starbucks Reports Q4 and Full Fiscal Year 2025 Results

  3. 3. About 1.1 million people took part in the 2026 Great Backyard Bird Count, counting birds for at least 15 minutes. How many bird checklists did they send in?

    The answer: about 468,000. They logged 8,257 species across 216 countries and regions.

    Napkin math
    1. 1.1Mpeople taking part
    2. ÷2people per checklist (families and friends count together)

    ≈550kchecklists

    The answer comes to about 468,000 checklists (New York Almanack). Without looking anything up, take 1.1 million people taking part, divided by 2 people per checklist (families and friends count together), and you get about 550,000 checklists. That comes out 1.2 times too high, and a guess that far off still scores 9.3 out of 10. The target is wider than it looks: every guess between 230,000 checklists and 940,000 checklists scores at least 7.0.

    Source: New York Almanack, Great Backyard Bird Count 2026 Results

  4. 4. How many wireless connections (phones, smartwatches, tablets and other devices on a cell plan) were there in the US in 2025?

    The answer: more than 600 million. That's roughly 1.8 for every American.

    Napkin math
    1. 330Mpeople in the US
    2. ×2devices each

    ≈660Mconnections

    The real answer is more than 600 million connections (Telecompetitor). On a napkin, take 330 million people in the US, times 2 devices each, and you get about 660 million connections. It's 1.1 times too high, which as a guess would still have scored 9.6 out of 10. The target is wider than it looks: every guess between 300 million connections and 1.2 billion connections scores at least 7.0.

    Source: Telecompetitor (reporting CTIA), Wireless data use in 2025 topped the entire 4G decade: Survey

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