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LifestyleEasy

Number of cups of coffee consumed daily in NYC

Estimate how many cups of coffee are consumed on an average weekday in New York City.

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Consumer TechHard

Mass of all smartphones sold last year

Compute the total combined mass (in metric tons) of smartphones sold worldwide in the past calendar year.

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Urban SystemsMedium

How many piano tuners operate in Chicago?

Estimate the number of full-time piano tuners that could sustainably operate in the Chicago metro area. Justify population assumptions, piano ownership rates, and servicing frequency.

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