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Best Guess · Puzzle #11 · Saturday, October 10

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 full-time-equivalent teachers worked in US public schools in fall 2022?

    The answer: about 3.2 million. Private schools had about another half a million full-time-equivalent teachers.

    Napkin math
    1. 50Mstudents in US public schools
    2. ÷20students per teacher

    ≈2.5Mteachers

    Source: National Center for Education Statistics, Fast Facts: Back-to-school statistics

  2. 2. How many pounds of ice cream (regular plus low-fat) did the average American eat in 2024?

    The answer: about 17.7 pounds. About two-thirds of it was regular, full-fat ice cream.

    Napkin math
    1. 52weeks a year
    2. ÷2weeks per pint (about a pound)

    ≈26pounds

    Source: USDA Economic Research Service, Dairy Data: Dairy products, per capita consumption, United States (annual)

  3. 3. How many 8-ounce glasses of plain water does the average US adult drink in a day?

    The answer: about 5.5 glasses. US kids and teens drank about half as much plain water as adults: 23 ounces a day.

    Napkin math
    1. 2bottles of water a day
    2. ×16.9ounces a bottle
    3. ÷8ounces a glass

    ≈4.23glasses

    Source: Centers for Disease Control and Prevention, Fast Facts: Data on Water Consumption

  4. 4. How many golf courses were there in the US at the end of 2025?

    The answer: about 16,000. They sit at about 14,000 golf facilities, since many clubs have more than one course.

    Napkin math
    1. 3,000counties in the US
    2. ×5golf courses a county

    ≈15kgolf courses

    Source: National Golf Foundation, Golf Industry Research

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