Why This Topic Matters
Grouping, Selection & Distribution
Allocate people or objects to groups under constraints — who can be together, how many each group holds, which attributes must be covered. Classic "pick a committee of 4" sets haven't appeared in recent CAT papers; what CAT actually runs is this skill in allocation form: distributing objects among people, assigning players to coaches, placing items into slots.
| The tested form | Year | What it looked like |
|---|---|---|
| Distribution of objects | 2021 | Ten objects split among five people under count rules |
| Coach–player allocation | 2024 | Eight players assigned to three coaches with parity, count and rating rules |
| Constrained grid placement | 2024 | Numbers 1–10 placed into a grid under row/column orderings |
The toolkit
- Anchor the total. Objects, players, or slots — write the total and force the group-size split before anything else. "How many" precedes "which."
- Partition by attribute. Parity, gender, department, city — when a rule says a group draws only from one pool ("only even-numbered"), compute each pool's size; small pools are your tightest constraints.
- Translate pair rules.
- "A and B can't be together" → they sit in different groups; in counting questions, split into cases by where A goes.
- "If X is selected, Y must be" → a conditional: it fires only when X is in; its contrapositive (no Y → no X) is free information.
- Min–max squeeze. "Each group at least 2, at most 4" plus a known total usually leaves only one or two size-splits — enumerate them as cases.
- Distinctness as a constraint. "All got different counts/ratings" combined with a fixed sum is powerful: distinct non-negative integers summing to has very few solutions. Use it to force values.
A worked mini-set
Fifteen prizes are split among A, B, C, D, E. Each gets at least 1; all five counts are different; B gets more than only D (i.e. B is second-lowest); A gets exactly 4.
- Five different positive integers summing to 15: since , the counts must be exactly {1, 2, 3, 4, 5} — no freedom at all. Distinctness + total has already decided how many; only who gets which remains.
- B is second-lowest ⇒ B = 2, and D = 1 (the only count below 2).
- A = 4 is given. So C and E hold {3, 5} between them — one further clue would finish the set.
The lesson: arithmetic on the totals eliminates most of the universe before any "who" reasoning starts.
Common traps
Jumping to "which" before "how many." In every recent CAT allocation set, the group sizes are forced (or nearly forced) by counts, parity pools, and min/max rules. Students who start placing individuals immediately branch into dozens of cases; students who count first branch into two or three.
- Forgetting a conditional's contrapositive — "if X then Y" also bans "X without Y."
- Treating "can't be together" as "must be apart in every question" — a new sub-question may add a hypothesis; re-read what each question fixes.
Checklist
- Write the total; force group sizes with min/max + distinctness
- Build attribute pools (parity, city, gender) and size them
- Convert pair rules; harvest contrapositives
- Case-split on the smallest pool, not the first clue
- Verify every rule in the final allocation
Sample Questions
15 practice questions
Sign in for full access
Create a free account to access all 15 practice questions on this topic.
CAT PYQ Spotlight
Actual CAT questions on this topic
Sign in for full access
Create a free account to access all 8 CAT PYQs on this topic.
Continue Your Prep