Estimation question

How do you decide how many cash registers you need for a new Walmart store?

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

Operational estimation combining expected customer traffic, average transaction time, and target wait time.

Estimate peak hour customer traffic for a typical store, for example 200 customers checking out during the busiest hour.
Estimate average checkout time per customer, for example three minutes including scanning and payment.
Calculate register throughput, each register can process 60 divided by 3 equals 20 customers an hour.
Divide peak demand by per register throughput to estimate registers needed, 200 divided by 20 equals 10 registers, then add a buffer for target wait time and self checkout mix.
Account for self checkout lanes reducing traditional register need, and state a final range combining both types.

Anchors on peak hour demand specifically, since sizing for average traffic would create long lines during the busiest periods, the actual design constraint.
Shows the throughput math clearly, 200 peak customers divided by 20 per register an hour equals 10 registers, then adds roughly 20 percent buffer for a comfortable wait time target.
Explicitly factors in self checkout lanes as a substitute for some traditional registers, since most modern stores mix both, changing the final register count.

Using average daily traffic instead of peak hour traffic, which would understaff during the busiest period.
No stated assumption for average checkout time per customer.
Ignoring self checkout as an alternative that changes the traditional register count needed.

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