In this guide
DILR does not reward knowing formulas. It rewards reading a set of conditions carefully, choosing a way to represent them, and pushing the deductions until the picture is complete. Those are trainable skills, but they grow through volume and review, not through theory.
It is also the section where scores swing most. One set solved fully can be worth 15 marks or more; one set half-understood can be worth nothing after negative marks. So a DILR plan has two goals: build the solving skill across set types, and build the judgement to choose which sets to solve.
What the section tests
Each set gives you a situation (a table with gaps, a tournament, a seating plan, a set of transactions) and five or six questions about it. You must understand the whole set before you can answer most of its questions. That makes the set, not the question, the unit of work.
Three skills sit under every set:
- Reading conditions exactly. "At least", "exactly", "immediately after", "not necessarily distinct". One misread word and every answer is wrong.
- Choosing a representation. A grid, a timeline, a table with totals, a tree of cases. The right diagram does half the work.
- Case handling. When a condition allows two possibilities, you split into cases and eliminate the one that breaks another condition.
Set types and the tool for each
| Set type | What it looks like | Tool to use |
|---|---|---|
| Tables with missing values | Totals and some cells given | Fill with row and column totals first |
| Bar, line and pie charts | Values over time or shares of a whole | Convert to a table of numbers |
| Caselets | Data in paragraphs | Build a table before any question |
| Arrangements | Seating, ordering, ranking | Grid or line with positions |
| Scheduling | Days, slots, sequences | Timeline with slots as columns |
| Games and tournaments | Matches, points, knockouts | Results matrix; points table |
| Venn and grouping | Overlapping sets, selections | Venn with every region labelled |
| Networks and routes | Paths, flows, costs | Diagram with flows on each edge |
| Binary logic | Truth-tellers and liars | Case table: assume and test |
| Maxima and minima | "At most", "at least" | Extreme cases, one variable at a time |
Many recent sets mix types, for example a table whose values must be deduced from logical conditions. For specific guides, start with tables and arrangements.
A six-month plan
| Phase | Weeks | Sets per day | Focus |
|---|---|---|---|
| Foundations | 1–6 | 2 | One set type per week; untimed; learn the tool for each |
| Range | 7–12 | 3 | Mixed types; 15 minutes per set cap; start a set log |
| Speed and selection | 13–18 | 3–4 | Timed sectionals twice a week; practise choosing sets |
| Mocks | 19–26 | 2 plus mocks | Full mocks weekly, then twice weekly; review each DILR section fully |
If you have less than six months, compress the first phase to three weeks, but do not skip it. Speed built on a weak method collapses under exam pressure.
A weekly shape in the range phase
| Day | Work |
|---|---|
| Mon–Fri | Three mixed sets, timed at 15 minutes each, reviewed the same day |
| Sat | One DILR sectional of four sets in 40 minutes |
| Sun | Re-solve the week's two worst sets without looking at solutions |
The Sunday re-solve matters most. A set you understood from a solution is not a set you can solve.
A five-step solving method
- Read the whole set once, including the questions. Note every condition in shorthand.
- Choose the representation: grid, timeline, table or diagram.
- Place the fixed facts first: anything that says "is" rather than "is not" or "before".
- Work the conditions: split into cases where needed, and kill cases that break a condition.
- Answer the questions, reading each for new conditions. Some questions add an "if", which applies to that question only.
Worked example: a scheduling set
This set was built for this guide and has exactly one solution.
Five colleagues, P, Q, R, S and T, each give one presentation on a different day from Monday to Friday. R presents on Wednesday or Thursday. S presents on the day immediately after T. Exactly one person presents between R and S. Q presents later in the week than R.
Step 1: shorthand. R = Wed or Thu. T then S, back to back. One day between R and S. Q after R.
Step 2: representation. A row of five slots, Mon to Fri.
Step 3: fixed facts. Only R's possible days are given, so split into two cases.
Step 4: cases.
| Case | Where S must be | Where T must be | Check "Q after R" | Result |
|---|---|---|---|---|
| R on Wed | Mon or Fri (one day between) | S on Mon is impossible, since T needs the day before; so S Fri, T Thu | Q must be Thu or Fri, both taken | Fails |
| R on Thu | Tue (Sat does not exist) | Mon | Q on Fri | Works; P takes the last day, Wed |
The solution.
| Mon | Tue | Wed | Thu | Fri |
|---|---|---|---|---|
| T | S | P | R | Q |
Questions.
- Who presents on Wednesday? P.
- How many people present between T and Q? Three: S, P and R.
- If the condition "Q presents later in the week than R" were removed, how many schedules would be possible? Four. With R on Wed, S and T are fixed on Fri and Thu, and P and Q can take Mon and Tue in either order (2 schedules). With R on Thu, S and T are fixed on Tue and Mon, and P and Q can take Wed and Fri in either order (2 schedules).
Question 3 shows why the method matters. A candidate who had listed the cases in a table answers it in seconds. A candidate who had found the solution by trial and error has to start again.
Tracking your progress
Keep a set log. It takes one minute per set and shows you what to practise next.
| Date | Set type | Time taken | Questions right / total | Got stuck at | Should I have chosen it? |
|---|---|---|---|---|---|
| 12 Jul | Scheduling | 11 min | 5 / 5 | Nowhere | Yes |
| 12 Jul | Tournament | 18 min | 2 / 6 | Misread "at least one draw" | No: too many cases |
After four weeks, sort the log by set type. The types with long times or low accuracy are next month's focus. The last column trains the selection judgement you will need in the exam; see DILR set selection.
Common planning mistakes
- Only solving sets you like. Everyone has a comfortable type. The exam will not.
- Reading solutions too early. Give a set at least 20 minutes in the foundation phase before you look.
- Starting mocks before the method is steady. Mocks measure; they do not teach.
- No review. An unreviewed set teaches you only that you got it wrong.
- Calculation neglect. DI sets need quick percentages and fractions. Ten minutes of calculation drill a day pays off.
What to do next
- Set up your set log today and fill it for every set you solve from now on.
- Pick the phase that matches your calendar and write the next four weeks into your planner.
- Solve the worked set above again tomorrow without looking, and time yourself.
- Choose one set type you avoid and do three sets of it this week, untimed.
A note on dates and numbers. Exam patterns, vacancies and schedules change from year to year. Always confirm the current details in the latest notification on the Indian Institutes of Management website .
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