Estimation question

Estimate the number of police officers in the US.

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

Whether the candidate can build a bottoms-up estimate using population, jurisdiction structure, and staffing ratio assumptions.

State scope: assume sworn police officers across the US, including local, state, and federal law enforcement.
Estimate the US population, roughly 335 million, and assume a general officer-to-population ratio around 2 to 2.5 officers per 1,000 residents, based on typical municipal staffing norms.
Multiply: 335 million times 2.2 per 1,000 gives roughly 735,000 officers from this baseline ratio.
Add a smaller adjustment for federal-level law enforcement (FBI, DEA, Border Patrol and similar), assumed at roughly 100,000 to 150,000 additional officers.
Land on a total estimate of roughly 800,000 to 900,000 officers, presented as a range.

Uses a per-capita staffing ratio as the core driver, a reasonable and explainable proxy for police staffing levels.
Separates local/state officers from federal-level law enforcement instead of treating all officers as one uniform category.
Presents a final range rather than a single overly precise number.

Guessing a total number directly without a clear per-capita ratio driving the calculation.
Ignoring federal law enforcement as a separate, additive category.

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