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Best Guess · Puzzle #29 · Wednesday, October 28

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 pounds of chicken per person were available to eat in the US in 2021 (boneless weight)?

    The answer: 68.1 pounds. Chicken beat beef, at 56.2 pounds per person, as the most available meat.

    Napkin math
    1. 0.5pounds a serving
    2. ×3servings a week
    3. ×52weeks a year

    ≈78pounds

    The answer comes to 68.1 pounds (USDA Economic Research Service). Without looking anything up, take 0.5 pounds a serving, times 3 servings a week, times 52 weeks a year, and you get about 78 pounds. That comes out 1.1 times too high, and a guess that far off still scores 9.4 out of 10. Because only the ratio counts, anything between 34 pounds and 140 pounds was worth 7.0 or more.

    Source: USDA Economic Research Service, Chicken leads U.S. per person availability of meat over last decade

  2. 2. How many boxes of Girl Scout Cookies are sold in a season?

    The answer: about 200 million. Those boxes add up to about $800 million in sales a year.

    Napkin math
    1. 130Mhouseholds in the US
    2. ×2boxes each a season

    ≈260Mboxes

    The true figure is about 200 million boxes (Fox Business). To reason it out, take 130 million households in the US, times 2 boxes each a season, and you get about 260 million boxes. It's 1.3 times too high, which as a guess would still have scored 8.9 out of 10. Any guess from 100 million boxes to 400 million boxes scores 7.0 or better, because the game only counts how many times off you are.

    Source: Fox Business, Girl Scout Cookies and what to know about the $800M business

  3. 3. How many breaths does an adult take in a day?

    The answer: about 17,000 breaths. That works out to more than 6 million breaths a year, according to the American Lung Association.

    Napkin math
    1. 15breaths a minute
    2. ×60minutes an hour
    3. ×24hours a day

    ≈21.6kbreaths

    The true figure is about 17,000 breaths (American Lung Association). Without looking anything up, take 15 breaths a minute, times 60 minutes an hour, times 24 hours a day, and you get about 22,000 breaths. That comes out 1.3 times too high, and a guess that far off still scores 9.0 out of 10. Any guess from 8,500 breaths to 34,000 breaths scores 7.0 or better, because the game only counts how many times off you are.

    Source: American Lung Association, How Your Lungs Get the Job Done

  4. 4. How thick are Saturn's main rings, typically, in feet?

    The answer: about 30 feet. Yet the ring system stretches up to 175,000 miles out from the planet.

    Napkin math: The rings are made of orbiting chunks of ice from dust-size to house-size, flattened by collisions into an incredibly thin sheet, perhaps only a few boulders deep.

    The true figure is about 30 feet (NASA Science). There's no tidy chain of numbers for this one, so the skill is a sense of scale: the answer is in the tens. The target is wider than it looks: every guess between 15 feet and 60 feet scores at least 7.0.

    Source: NASA Science, Saturn: Facts

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