Estimation Case: Sizing a Day of Air Travel at San Francisco International Airport

Estimate how many people fly into or out of San Francisco International Airport (SFO) on a single day. ```hint Pick what to count from Decide whether to build the number from the airport's flights and seats or from how often people travel, and keep the other route as a cross-check. ``` ### Clarifying Questions - Should a traveler who connects at SFO, arriving on one flight and leaving on another, count once or twice? - Do airline crew count as people flying, or only passengers? - Is this a typical day, or a peak day such as the start of a holiday weekend? - Do you want a single number, or a range with the assumptions that drive it? ### What a Strong Answer Covers - A clear definition of who is counted, including connecting travelers and crew - An equation broken into factors, each assumption labeled and justified - Clean arithmetic with round numbers - A sanity check through an independent method or a known reference point - How the figure changes by season and day of week, and which assumption moves it most ### Follow-up Questions - Which single assumption is your answer most sensitive to, and what one piece of data would narrow it down? - Using your number, how many security screening lanes would SFO need in its busiest morning hour? - How would you estimate what share of these travelers are only connecting rather than starting or ending a trip in the Bay Area?