Estimation question

How would you estimate the total number of cars right now in Highway 101 between San Francisco and Mountain View?

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

Structured estimation applied to a physical, real-world scenario with clear geographic bounds.

Clarify scope: the stretch of Highway 101 between San Francisco and Mountain View, roughly 35 to 40 miles, at a given moment.
Estimate average traffic density per lane per mile based on typical highway spacing, e.g. one car per 100 to 150 feet during moderate traffic.
Estimate the number of lanes in each direction, assumed at 4 to 5 lanes each way for this stretch.
Multiply density per lane-mile by total lane-miles (distance times lanes times both directions) to get a total car count.
Adjust the estimate for time of day, since rush hour density is much higher than off-peak.
State the final estimate as a range tied to a specific time-of-day assumption.

States the distance and lane count assumptions explicitly rather than guessing silently.
Uses a grounded car-spacing assumption, e.g. one car per 120 feet in moderate traffic, to derive density.
Shows the full multiplication: distance times lanes times cars per lane-mile, so the logic is auditable.
Provides a range for rush hour versus off-peak rather than one static number.

Not stating the distance or lane count assumptions before estimating.
Giving one number with no acknowledgment that traffic density varies hugely by time of day.

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