Interviewer view · keep this screen to yourself

Is a new player worth what the game pays to win them?

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.

Lanternfox (a fictional studio in Singapore) runs a free-to-play mobile game. It pays USD 2.50 in advertising for each new install. 4 percent of new players ever pay, and a paying player spends USD 60 over their life in the game. The app store keeps 30 percent of in-game purchases. Ads shown to players who never pay bring USD 0.40 per install, and servers and live operations cost USD 0.20 per install. Should Lanternfox spend more on advertising, and what would change the answer?

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.

Value of one install against the cost to win it
- Money from players: share who pay x lifetime spend x share kept after the store fee
- Money from ads shown to players who do not pay
- Costs per install: live operations, and the advertising paid to win the install
- Levers: the store fee (a web shop), payer conversion, lifetime spend

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: Player spending per install
What a strong candidate does: 4 percent of installs pay, and each payer spends USD 60.
In-game spending per install (USD): 0.04 × 60 = 2.4
Step 2: Share kept after the store fee
What a strong candidate does: The app store keeps 30 percent.
Net in-game revenue per install (USD): 2.4 × (1 - 0.3) = 1.68
Step 3: Lifetime value per install
What a strong candidate does: Add ad revenue and take off live operations.
Lifetime value per install (USD): 1.68 + 0.4 - 0.2 = 1.88
Step 4: Against the cost of an install
What a strong candidate does: Each install costs USD 2.50 of advertising.
Profit or loss per install (USD): 1.88 - 2.5 = -0.62
Step 5: Half of spending moves to a web shop
What a strong candidate does: Payments on its own website cost about 5 percent instead of 30 percent, for half of the spending.
Lifetime value per install with a web shop (USD): 2.4 × (0.5 × 0.7 + 0.5 × 0.95) + 0.4 - 0.2 = 2.18
Step 6: Web shop and better conversion together
What a strong candidate does: If a better first session also lifts payer conversion to 5 percent, spending per install is USD 3.00.
Lifetime value per install, both levers (USD): 0.05 × 60 × 0.825 + 0.4 - 0.2 = 2.67

The recommendation to listen for

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

Lanternfox should not raise its advertising budget yet, because each install brings back only USD 1.88 against USD 2.50 paid to win it, a loss of USD 0.62 per new player. First, moving half of player spending to a web shop lifts the value to USD 2.18, which is still short. Second, only both levers together, the web shop and payer conversion of 5 percent, lift the value to about USD 2.68, above the cost of an install. The risk is that web shop links push some players away and that store rules keep changing by country. As a next step, test the web shop and a better first session on a small group of players, and grow advertising only in channels where the install cost is below the measured value.

Risks a strong answer names: Store rules on links to outside payments differ by country and keep changing; Lifetime spend is an estimate until players have been in the game for many months.

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.

Next: another case in Partner mode

Swap roles and run the next case, so you both practise answering and scoring.

Run the next case: Same bets, different tax: where should a sportsbook spend its marketing? Choose another case