Interviewer view · keep this screen to yourself

Standard: Wadi Telecom: size the home fiber market, then build or rent?

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.

First, estimate how many homes in Oman have fiber broadband. Then: Wadi Telecom, an Omani operator, can extend fiber to 100,000 more homes at OMR 300 per home passed. It expects 40 percent of those homes to sign up, paying OMR 25 a month, with a 60 percent contribution margin. Should it build?

Format note: Difficulty: Standard. Format: market-sizing opener, then a business question. Industry: Telecom. Region: Oman. Interview length: about 30 minutes. The company is fictional and all figures are illustrative.

2. Answers to clarifying questions

Give these answers only if the candidate asks. If they ask something not listed, give a sensible answer or say it does not matter here.

If asked: Homes only, or businesses too?
Answer: Homes only.
If asked: How many households are there, and how many can get fiber today?
Answer: Use about 1,000,000 households, rounded and illustrative; about 70 percent can get fiber.
If asked: Where fiber is available, how many homes take it?
Answer: About half.
If asked: For the business question, how long does fiber last and what discount rate should I use?
Answer: Fiber lasts 20 years or more; use 8 percent. At 8 percent, OMR 1 a year is worth about OMR 9.82 today over 20 years, and about OMR 5.75 over 8 years.

3. The hypothesis a strong candidate states

Listen for an early, testable guess like this one. It does not need to match word for word.

Fiber take-up is limited by where the network reaches. My hypothesis is that the market is several hundred thousand lines, and that for a new area building pays off only if enough homes sign up.

4. 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.

Size the market, then compare build with rent
- Households x share with fiber available x take-up
- Key: Build: capital cost versus yearly contribution
- Rent: use the open-access network instead

5. 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: Homes with fiber
What a strong candidate does: About 70 percent of about 1,000,000 households can get fiber, and about half of those take it.
Fiber lines: 1,000,000 × 0.7 × 0.5 = 350,000
Step 2: Yearly contribution if Wadi builds
What a strong candidate does: 40,000 subscribers at OMR 25 a month and a 60 percent margin.
Contribution (OMR a year): 100,000 × 0.4 × 25 × 12 × 0.6 = 7,200,000
Step 3: Payback
What a strong candidate does: Building costs OMR 30 million (100,000 homes at OMR 300 each).
Payback (years): 100,000 × 300 ÷ (100,000 × 0.4 × 25 × 12 × 0.6) = 4.17
Step 4: Curveball: rent from the open-access network
What a strong candidate does: Interviewer: "Oman's national open-access fiber network offers to rent Wadi access to the same homes for OMR 10 per subscriber a month, with no build cost." When renting, Wadi also avoids network running costs, so its margin before rent would be higher than 60 percent; keep 60 percent to be conservative. Yearly contribution if Wadi rents:
Contribution when renting (OMR a year): 100,000 × 0.4 × (25 × 0.6 - 10) × 12 = 2,400,000
Step 5: Build over the asset life
What a strong candidate does: Net present value over 20 years at 8 percent: yearly contribution times 9.82, minus the build cost.
Build NPV (OMR): 7,200,000 × 9.82 - 30,000,000 = 40,704,000
Step 6: Rent over the same period
What a strong candidate does: No build cost.
Rent NPV (OMR): 2,400,000 × 9.82 = 23,568,000
Step 7: On a short horizon
What a strong candidate does: Over only 8 years (factor 5.75), building minus renting is negative, so renting wins on a short view.
Build minus rent over 8 years (OMR): (7,200,000 - 2,400,000) × 5.75 - 30,000,000 = -2,400,000
Step 8: Break-even take-up
What a strong candidate does: Each subscriber earns OMR 15 a month of contribution when Wadi builds, against OMR 5 when it rents. Building wins over 20 years if those extra OMR 10 a month cover the build cost, which needs this take-up:
Break-even take-up (%): 30,000,000 ÷ (10 × 12 × 9.82) ÷ 100,000 × 100 = 25.46

The recommendation to listen for

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

Oman has roughly 350,000 homes on fiber. Wadi should build where it is confident take-up will be well above about 25 percent, and rent elsewhere. First, over fiber's 20-year life and at 8 percent, building is worth about OMR 40.7 million today against about OMR 23.6 million for renting, and it pays back in about 4.2 years. Second, on a short 8-year view renting comes out ahead, so the case for building rests on the long asset life. Third, building beats renting only if take-up exceeds about 25 percent; the expected 40 percent gives a margin of safety in dense neighborhoods, while in areas with uncertain demand Wadi should rent from the open-access network first and build later if take-up proves high.

Risks a strong answer names: Take-up below 40 percent would stretch the build payback; Rival price cuts could lower the OMR 25 monthly price.

Next steps: Map expected take-up by neighborhood; Negotiate rental terms with the open-access network as a fallback.

Strong versus weak

A strong answer

Built a clean sizing chain, compared build and rent over the asset life with discounting, found the break-even take-up, and tied the choice to take-up by area.

A weak answer

Sized the market with no stated assumptions, then said "build, because owning the network is strategic," without numbers.

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.