Estimation & sizing questions.

68 estimation & sizingquestions from the bank — open to read. Pick one and practice it out loud; a coach note comes back in seconds.

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All 68 questions

Estimate how many YouTube videos are uploaded per minute globally.Breaking the problem downMid–seniorHow many cups of coffee does a typical Starbucks store sell in a day?Reasonable assumptionsEntry–midEstimate the total revenue of all NYC bagel shops in a typical year.Breaking the problem downEntry–midEstimate the total weight of all the food consumed in the US in a single day.Sanity Checking the order of magnitudeMid–seniorHow many flights are in the air over the continental US at any given moment?Quick mental mathMid–seniorEstimate the annual ad spend on a major social platform's home feed. What's your confidence level?Communicating uncertaintyMid–seniorHow many gym memberships are sold in the US in January?Breaking the problem downEntry–seniorEstimate the total amount of cash that's withdrawn from US ATMs in a typical week.Reasonable assumptionsMid–seniorHow many windows are in your hotel chain's flagship building? Walk me through your estimate.Quick mental mathEntry–midEstimate Amazon's daily package delivery count in the US. Then sanity-check against any anchor you can think of.Sanity Checking the order of magnitudeMid–seniorHow many songs are streamed on Spotify per day?Breaking the problem downMid–seniorEstimate the number of unique paying customers a typical mid-market SaaS company has.Reasonable assumptionsMid–seniorHow much energy does a major data center use in a year?Quick mental mathSenior–staff+Estimate how many pages of US legal opinions are published in a year.Breaking the problem downMid–seniorEstimate the GDP contribution of all the AI startups founded in the last 24 months.Communicating uncertaintySenior–leadershipHow many people visit a typical national park in a peak summer week?Reasonable assumptionsEntry–seniorEstimate the number of credit card transactions processed in the US during the Black Friday weekend.Quick mental mathMid–seniorEstimate the total dollars spent on home renovation in the US in a year. Then check it against any cross-reference you can think of.Sanity Checking the order of magnitudeSenior–staff+How many doctors' appointments happen in the US in a typical week?Breaking the problem downMid–seniorEstimate the total developer hours spent annually maintaining open-source code globally.Reasonable assumptionsSenior–leadershipEstimate the number of pizzas delivered in NYC on a typical Friday evening.Quick mental mathEntry–midEstimate how much money venture capital firms collectively invested in seed-stage AI startups last year.Communicating uncertaintySenior–leadershipEstimate the total miles driven by Uber drivers in a single city in a day.Breaking the problem downMid–seniorEstimate the number of emails sent by a typical knowledge-worker in a year.Reasonable assumptionsEntry–midEstimate how many days it would take to repaint every surface in a 200,000-square-foot office building.Quick mental mathMid–seniorEstimate the total US revenue of dog grooming services. Then check it against pet ownership statistics if you can.Sanity Checking the order of magnitudeMid–seniorHow much storage does a single hour of a popular streaming video service occupy globally?Breaking the problem downSenior–staff+Estimate the total number of square feet of office space in Manhattan.Reasonable assumptionsMid–seniorEstimate the number of meals served by all McDonald's globally in a single day.Quick mental mathEntry–midEstimate the annual cost to a major airline of fuel for its widebody fleet. Where would your answer be most fragile?Communicating uncertaintySenior–leadershipEstimate how many gallons of gasoline are sold at a typical suburban gas station in a week.Breaking the problem downEntry–midHow many tennis balls fit inside a school bus? State your key assumptions clearly.Reasonable assumptionsEntry–midEstimate the number of smartphones currently in use in California. Does your answer pass a basic sanity check against the state's population?Sanity Checking the order of magnitudeEntry–midA movie theater has 8 screens. Estimate total ticket revenue for a typical Saturday. Walk me through your mental math.Quick mental mathEntry–midEstimate the number of pizzas delivered in Manhattan on a typical Friday night.Breaking the problem downEntry–midHow many electric vehicle charging stations currently exist in California? Walk me through your reasoning.Reasonable assumptionsMid–seniorEstimate the total number of credit card transactions processed in the US on Black Friday.Breaking the problem downMid–seniorHow many data centers does AWS operate globally? Give me your best estimate and confidence interval.Communicating uncertaintyMid–seniorEstimate the number of ride-share trips taken in Los Angeles during a typical weekday.Reasonable assumptionsEntry–midHow many customer support tickets does a major airline handle per day? Sanity-check your answer.Sanity Checking the order of magnitudeMid–seniorEstimate the total square footage of warehouse space Amazon uses in the US.Breaking the problem downSenior–leadershipHow many prescriptions are filled at US pharmacies in a typical day?Quick mental mathEntry–midEstimate the number of active software engineers currently employed at Google worldwide.Reasonable assumptionsMid–seniorHow many baby diapers are sold in the US each year? Walk through your assumptions.Breaking the problem downEntry–midEstimate the total value of venture capital deployed in the US last year. What's your confidence level?Communicating uncertaintySenior–leadershipHow many hours of content does Netflix add to its platform each month globally?Reasonable assumptionsMid–seniorEstimate the number of gallons of gasoline sold at US gas stations on a typical summer day.Quick mental mathEntry–midHow many job applications does a Fortune 500 company receive per year? Sanity-check against hiring volume.Sanity Checking the order of magnitudeMid–seniorEstimate the total number of hotel rooms available in Las Vegas.Breaking the problem downEntry–midHow many lines of code are in the Windows operating system? Give me a range and explain your reasoning.Communicating uncertaintySenior–leadershipEstimate the number of MRI scans performed in the US each day.Reasonable assumptionsMid–seniorHow many smartphones are currently in active use worldwide? Walk me through your estimate.Breaking the problem downMid–seniorEstimate the total annual revenue of all McDonald's locations in the US.Quick mental mathEntry–midHow many cybersecurity incidents does a major bank detect and respond to each month?Reasonable assumptionsSenior–leadershipEstimate the number of shipping containers that pass through the Port of Los Angeles each day. Then sanity-check it.Sanity Checking the order of magnitudeMid–seniorHow many patents does IBM file globally in a typical year? Give me your best estimate and confidence interval.Communicating uncertaintySenior–leadershipEstimate the total number of employees working in investment banking across all Wall Street firms.Breaking the problem downMid–seniorHow many tons of plastic waste does the US generate each year?Reasonable assumptionsMid–seniorEstimate the number of API calls Stripe processes per second during peak shopping hours. What assumptions are you making?Breaking the problem downSenior–leadershipEstimate the total annual fee revenue of the US mutual fund and ETF industry.Breaking the problem downMid–seniorEstimate the assets a typical US financial advisor manages for clients.Reasonable assumptionsEntry–midYour firm cuts the expense ratio on a $500 billion index fund family by 2 basis points. Estimate the revenue impact, and how much new AUM it takes to offset it.Quick mental mathMid–seniorEstimate the total assets held in US 401(k) plans.Sanity Checking the order of magnitudeMid–seniorEstimate how many homes are sold in the United States in a year, and the total commission pool that creates.Breaking the problem downMid–seniorA 280-unit apartment building opens in a metro of one million people. Estimate a reasonable monthly absorption rate and how long it takes to reach 95% occupancy.Reasonable assumptionsMid–seniorA rental house costs $380,000 and rents for $2,400 a month. Roughly, in your head: what's the gross yield, and does it cash-flow with 20% down at a 7% mortgage?Quick mental mathEntry–midEstimate the total square footage of office space in Manhattan, and sanity-check your answer from a second direction.Sanity Checking the order of magnitudeMid–seniorEstimate how many licensed real estate agents are active in the US, and what share closed more than five transactions last year. Be explicit about your confidence in each step.Communicating uncertaintyMid–senior