NinetynineInteger solutions of x + y + z = n with lower or upper bounds
CAT has tested this idea 5 times across 4 papers, from 2017 to 2022. Solve one, and the others are the same method with different numbers or wording, which is why repeated concepts are the most efficient thing to practise.
| Question | What it asks | Answer |
|---|---|---|
| CAT 2017 Slot 2 · QA Q29 | 8 pens, minimums 1, 2, 3 | 6 |
| CAT 2021 Slot 2 · QA Q1 | three item types, each with minimums, multiply counts | 1000 |
| CAT 2017 Slot 1 · QA Q32 | 7 erasers among 4 kids, each 1 to 3 | A |
| CAT 2022 Slot 1 · QA Q2 | 20 balloons, even positive amounts each | 84 |
| CAT 2017 Slot 1 · QA Q25 | x − y − z = 25 with upper bounds | B |
Part of Permutations & Probability (21 questions since 2017).