What this exercise is testing in forty-five minutes
Graduate assessment centres use the case study exercise to see how you handle more information than you can absorb, under a clock, while still reaching a decision. The pack is often deliberately oversized: emails, a finance table, a customer complaint, a news article, a board paper. Some documents matter, some are background, and one or two may be out of date or contradict each other.
How the written answer is marked, including putting the recommendation first and stating assumptions you could check, is covered in the take-home and case study guide. This page is about the forty-five minutes before you have an answer, which is where most candidates lose the exercise.
A time plan you can hold to
Write the plan at the top of your scrap paper before reading anything, and check the clock against it.
| Minutes | What you do |
|---|
| 0 to 3 | Read the task itself: who wants the answer, what decision, what format and length |
| 3 to 10 | Skim every document: title, author, date and one line on relevance; mark each A, B or C |
| 10 to 22 | Read the A documents closely and copy the key figures into one table |
| 22 to 27 | Decide, and write the recommendation sentence before anything else |
| 27 to 40 | Write the reasons, risks, mitigations and next steps |
| 40 to 45 | Check arithmetic, check you answered the question asked, tidy |
The blocks add up to forty-five minutes. If the exercise gives you a different time, scale the blocks but keep the order. If you overrun the reading block, cut close reading, not the writing block, because an unfinished answer cannot score on decision-making at all.
Triage the pack before you read it
Reading document one to the end, then document two, is how the time disappears. Skim first. The task tells you what decision is needed, so a document is an A if it changes that decision, a B if it gives useful context, and a C if it is background you can ignore.
Dates and authors matter. A short email from last week can override a long report from last year, and an operations manager's capacity figures may contradict a sales forecast. When two documents disagree, do not silently pick one. Say which figure you used and why, for example because it is more recent or comes from the team that owns the number.
Working one pack: choosing between two suppliers
Suppose the request asks you to recommend one of two delivery suppliers for the next two years. The A documents give you these figures, which you copy into one table:
Supplier A: 40,000 a year, fixed for two years, 92% on time
Supplier B: 34,000 in year one; a recent email says +15% from year two; 88% on time
Volume: about 500 deliveries a year
Finance note: each late delivery costs about 50 in refunds
Two-year price
A: 40,000 x 2 = 80,000
B: 34,000 + (34,000 x 1.15) = 34,000 + 39,100 = 73,100
B is cheaper by 6,900 (3,450 a year)
Late deliveries a year
A: 500 x 0.08 = 40 -> 40 x 50 = 2,000
B: 500 x 0.12 = 60 -> 60 x 50 = 3,000
B costs an extra 1,000 a year, 2,000 over two years
Net two-year saving with B: 6,900 - 2,000 = 4,900
Break-even: B stops being cheaper if a late delivery costs more than
3,450 / 20 extra late deliveries = 172.50 each
Two details decide this case. First, the price-rise email is easy to miss, and a candidate who ignores it puts B's two-year price saving at 12,000 instead of 6,900. Second, the refund figure only captures direct cost. If the complaints document shows late deliveries are losing customers, the true cost per late delivery could exceed the break-even, and the answer flips. That is the number to name as your main uncertainty.
A recommendation built on that working might read:
I recommend Supplier B. Over two years it is about 4,900 cheaper after allowing for its price rise and its higher late-delivery refunds. The main risk is reliability: B is late more often, and if lost customers make each late delivery cost more than about 170, A becomes the better choice. I would sign with B on a contract that allows a review after six months against an on-time target.
Why reading everything leaves no time to decide
The trap in this exercise is mistaking thoroughness for quality. Candidates who read every page closely produce a summary of each document and run out of time before deciding, or finish with "both options have merits". At an assessment centre, assessors often have a marking guide that lists the facts in the pack that should drive the choice, and a fence-sitting answer scores poorly on judgement whichever facts it mentions.
A clear recommendation that turns out to be the less favoured option still scores, provided the reasons trace to the documents and the risks are honest. A balanced summary with no recommendation does not answer the request at all.
When there is a presentation or a twist
Some assessment centres follow the written exercise with a short presentation to an assessor, who may challenge your choice or hand you new information. Treat new information the way you treated the pack: does it change the decision or only a risk? If it changes the decision, say so plainly and explain why. Changing your mind for a good reason is a strong signal, not a weak one. A related format, the in-tray or e-tray exercise, asks you to prioritise a queue of emails rather than make one recommendation, but the same skimming and triage habits apply.
A case study exercise is marked on the decision you reach and the evidence you cite. Read only what you need to decide well, then decide.
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