Interviewer view · keep this screen to yourself

One problem, three roles: online grocery orders that lose money

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.

Fictional and illustrative. A supermarket chain in the Netherlands takes 20,000 online orders a week. The average basket is EUR 60 and the chain keeps 25 percent of it as gross margin (what is left after paying for the goods). Each order costs EUR 7 to pick in the store, EUR 9 to deliver and EUR 1 in payment fees. There is no delivery fee today. A consultant, the chain's product manager for the app, and an investor looking at the chain each meet this problem. What does each of them conclude?

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.

Weekly contribution from online orders = orders x (margin per order minus cost to serve per order)
- Margin per order
  - Basket size x gross margin
  - Any delivery fee
- Cost to serve per order
  - Picking
  - Delivery
  - Payment
- Orders a week, and how they react to a fee

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: Margin per order
What a strong candidate does: A EUR 60 basket at a 25 percent gross margin.
Gross margin per order (EUR): 60 × 0.25 = 15
Step 2: Cost to serve per order
What a strong candidate does: Add picking at EUR 7, delivery at EUR 9 and payment at EUR 1.
Cost to serve per order (EUR): 7 + 9 + 1 = 17
Step 3: Contribution per order
What a strong candidate does: Margin per order minus the cost to serve it.
Contribution per order (EUR): 15 - 17 = -2
Step 4: Contribution per week
What a strong candidate does: Contribution per order across 20,000 orders a week.
Weekly contribution (EUR): -2 × 20,000 = -40,000
Step 5: Test one fix: a EUR 3 delivery fee
What a strong candidate does: Suppose a EUR 3 fee is added and one order in ten is lost. Work out the new weekly contribution on the orders that remain.
Weekly contribution with the fee (EUR): (15 + 3 - 17) × 20,000 × 0.9 = 18,000

The recommendation to listen for

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

Online orders lose about EUR 40,000 a week because each order costs EUR 17 to serve and earns EUR 15 of margin. All three roles agree on that number, but each draws a different so what. The consultant says: test a EUR 3 fee before cutting the service. The reason is that the fee would turn the loss into a gain of about EUR 18,000 a week, even if one order in ten is lost. The product manager says: I will test the fee on a share of customers and watch order numbers and basket size. I will also try a minimum basket, because a bigger basket spreads about the same EUR 17 over more margin. The investor says: pricing can fix this, so the online losses should not lower what I would pay for the chain. I will still ask whether rivals can afford free delivery for longer than the chain can.

Risks a strong answer names: If more than one order in ten is lost, the gain shrinks; Delivery cost per order may fall as volume grows, which changes the answer.

Next steps: Test the fee on a sample of customers for four weeks; Measure how many lost orders move to the physical stores instead.

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: A food group has AED 300 million and two units that want AED 200 million each Choose another case