Estimation question

How many unique people write reviews on Amazon every month?

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 grounded in Amazon's known scale and typical reviewer behavior patterns.

Pick a method: estimate Amazon's active monthly buyer base, then apply a realistic review-writing conversion rate.
Assume roughly 200 million active US buyers monthly, as a reasonable order of magnitude for Amazon's scale.
Assume a small share, roughly 2 to 5 percent, actually write a review in a given month, since most buyers never review.
Multiply the buyer base by the review rate to estimate unique reviewers monthly.
Sanity check against known review volume patterns, since Amazon receives millions of reviews across all products monthly.
State the final estimate as an order of magnitude in the low millions of unique reviewers monthly.

Anchors on a specific, defensible buyer base assumption, roughly 200 million active US buyers, rather than guessing globally.
Applies a realistic low conversion rate for review writing, since most buyers never leave reviews, and states it openly as an assumption.
Cross checks the resulting figure against known scale of total reviews on Amazon to sanity check the math.
Lands on an order of magnitude, low millions, with the calculation visible rather than a single unexplained guess.

Assuming most buyers write reviews, which vastly overstates the real conversion rate.
Giving a global estimate without clarifying scope, since behavior varies a lot by country.

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