In a small business-case interview, clarify the decision, work through the provided numbers and state what the case cannot establish. A reasonable conditional answer is better than an unsupported claim of certainty.

This original practice case concerns fictional library opening hours. It is not financial or operational advice, and its numbers do not describe a real library.

Read the case

Fictional proposal: add one two-hour evening session each week.
Provided estimate: 12 additional visits per session.
Provided staffing assumption: two staff members for the session.
Not provided: actual demand, staffing cost, safety requirements,
visitor needs or impact on existing opening hours.

The estimated visits are an assumption in the prompt, not observed demand. Keep that distinction throughout the answer.

Question: what do you clarify first?

Illustrative answer: “I would ask what outcome the library wants: access for people who cannot attend existing hours, more total visits or another service goal. I would also confirm whether staffing and safety requirements permit a trial.”

The objective changes the evaluation. Moving existing visitors into a later slot may improve access for some people without increasing total visits. Neither measure is automatically the only useful one.

Question: what can you calculate?

Under the stated estimate, twelve visits over two hours is an average of six visits per hour. With two staff members for two hours, the session uses four staff-hours. Those calculations describe the assumptions; they do not show whether the session is worthwhile.

Do not infer a cost per visit without a cost figure. Do not assume every additional visit requires the same amount of staff attention. Explain which missing input prevents the next calculation.

Question: would you approve the extension?

Illustrative answer: “I would not recommend a permanent extension from these estimates alone. If the responsible team confirms staffing and safety feasibility, I would suggest a bounded trial with a clear access goal and a review point. I would compare observed use and service value with the resources required.”

This is a conditional recommendation. It does not bypass the real organization's approval process or assert that a trial is always the best option.

Question: what should the trial measure?

  • Actual attendance and use of services.
  • Whether visitors could attend existing sessions.
  • Operational constraints and staff workload.
  • Any effect on other opening hours.
  • The evidence needed for the agreed decision.

Collect only appropriate information through the organization's supported process. A practice case is not a reason to gather unnecessary personal data.

How should you handle a changed assumption?

If expected demand falls or staffing is unavailable, revise the recommendation. Consider a different session or another way to meet the access goal. Do not defend the original proposal after the conditions that supported it have disappeared.

Finish by separating known inputs, calculations, assumptions and the next decision. That gives the interviewer a transparent reasoning path rather than a confident answer built on missing information.

References and next practice

careerservices.fas.harvard.edu — career

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