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Cost per drop for a courier in Dubai

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.

A courier van in Dubai costs AED 250 a day for the driver, AED 150 for the van lease and insurance, and AED 60 for fuel. The driver attempts 100 deliveries a day, and 8 percent fail (nobody home, wrong address). What is the cost per successful drop? What happens if failed deliveries fall to 3 percent?

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.

Cost per drop = daily van cost divided by successful drops per day
- Daily van cost = driver + van + fuel
- Successful drops = attempts x (1 minus failure rate)

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: Daily van cost
What a strong candidate does: Driver, van and fuel.
Daily van cost (AED): 250 + 150 + 60 = 460
Step 2: Cost per drop at 8 percent failures
What a strong candidate does: 92 successful drops.
Cost per drop (AED): 460 ÷ (100 × (1 - 0.08)) = 5
Step 3: Cost per drop at 3 percent failures
What a strong candidate does: 97 successful drops.
Cost per drop at lower failure (AED): 460 ÷ (100 × (1 - 0.03)) = 4.74

The recommendation to listen for

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

The courier should cut failed deliveries, because lowering them from 8 to 3 percent cuts cost per successful drop from AED 5 to about AED 4.74, about 5 percent. First, the van costs AED 460 a day whether a drop succeeds or not. Second, each failed parcel also needs a second trip later, so the true saving is larger. The risk is that delivery time slots or lockers cost more than they save. As a next step, test delivery time slots and pickup points on a few routes.

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.