Estimation question

Estimate the number of flights currently in operation.

Practice this question out loud. An AI interviewer asks it, follows up like a real interviewer would, and scores your answer. Type or speak.

What this question tests

Estimation skill: structured decomposition of a Fermi problem with clearly stated, reasonable assumptions.

Clarify scope: commercial passenger flights in the air at a given moment, worldwide.
Estimate total daily flights globally, using an assumed figure like 100,000 flights per day as a reasonable anchor.
Estimate average flight duration, e.g. assume 2 hours on average across short and long haul.
Estimate what fraction of the day flights are airborne versus on the ground, based on average duration versus a 24-hour day.
Combine the numbers: daily flights times average duration divided by 24 hours to estimate flights in the air at once.

States each assumption explicitly and flags it as an assumption, e.g. 'I will assume 100,000 daily flights.'
Shows the math clearly: 100,000 times 2 hours divided by 24 hours equals roughly 8,000 flights airborne at once.
Sanity-checks the result against a known reference point, like flight-tracking sites reporting similar figures.
Explains how the estimate would change for peak versus off-peak hours.

Guessing a final number with no visible decomposition or reasoning.
Using clearly unreasonable assumptions, like a 10-hour global daily flight average.
Not sanity-checking the final answer against any real-world reference.

Chapters of the AI PM course that teach what this question tests.