Interviewer view · keep this screen to yourself

Yearly revenue of one hair salon in Singapore

You run the case. Read the prompt, answer questions from the notes below, and share data only when the candidate asks for it or gets stuck. Score at the end.

Case timer

00:00

Target length:

1. Read the prompt aloud

Read it slowly, then pause. Let the candidate ask questions before they structure.

Estimate the yearly revenue of a typical neighborhood hair salon in Singapore.

2. Answers to clarifying questions

This case has no scripted clarifying answers. Answer from the prompt, and say "assume what you think is reasonable" if the prompt does not cover it.

3. A model structure

Compare the candidate's structure with this one. A different split can be just as good if it is clean and fits the problem.

Revenue = chairs x clients per chair per day x days open x average price
- Clients per year = chairs x clients per chair per day x days open
- Revenue = clients per year x average price

4. The working, step by step

Each step shows how a strong candidate works it out. Share a new fact from it only when the candidate asks or is stuck, and let them do the math: the result in the dark box is what they should reach.

Step 1: Clients per year
What a strong candidate does: Assume 4 chairs, 8 clients per chair on an average day (some slow, some busy), and 300 open days a year.
Clients per year: 4 × 8 × 300 = 9,600
Step 2: Revenue
What a strong candidate does: Assume an average price of SGD 30 per visit across cuts, colour, and other services.
Revenue per year (SGD): 9,600 × 30 = 288,000

The recommendation to listen for

At the end, say: "The CEO walks in. What is your recommendation?"

My answer is about SGD 290,000 a year, because a typical salon serves about 9,600 clients a year at SGD 30 each, which gives SGD 288,000. That rests on 4 chairs, 8 clients per chair a day and 300 open days, so the estimate is easy to check. The main risk is the SGD 30 average price, since colour and other services cost more than a basic cut. As a next step, test the figure by visiting two or three salons and noting chairs, busy hours and prices.

Score the candidate

Score each criterion from 1 to 5. A 2 or a 4 sits between the descriptions.

This case has no exhibit. Score Exhibit reading on how the candidate used the data you gave them: did they pick out the number that matters and say what it means?

Structuring

1: No clear structure, or a memorized framework that does not fit the problem.
3: A sensible structure, but with some overlap, a gap, or no clear priority.
5: A structure built for this problem, with no overlap and no gaps, a stated hypothesis, and a clear first step.

Math

1: Frequent errors, no units, or needed heavy help to finish.
3: Right answers but slow or messy working, or one error caught late.
5: Accurate and clearly narrated, with units, a sense check, and what the number means.

Exhibit reading

1: Read the chart aloud without finding the number that matters.
3: Found the key number but gave only part of the so-what.
5: Pulled the right number quickly and said what it means for the case.

Synthesis

1: Summarized what was done, with no clear answer.
3: Gave an answer, but with weak reasons or no next step.
5: Answer first, then two or three reasons with numbers, the main risk, and next steps.

Communication

1: Hard to follow: long silences, no signposting.
3: Clear most of the time, with some rambling.
5: Calm and concise, signposted each step, and checked in with the interviewer.

Total

0 out of 25

Score all five criteria to see the band and the feedback template.