IOQM · Mathematics · Combinatorics
Counting Principles
Addition and multiplication principles, bijective counting and double counting.
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- Previous papers: 10 official question papers from HBCSE-TIFR (Mathematical Olympiad Cell) — 2025, 2024, 2022-23, 2021-22 and 1 earlier year.
- Practice: 2 answer-checked practice questions on Counting Principles for IOQM — practise them.
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Take a full mock →Q1 · Counting Principles · EASY
A committee of 5 people is to be formed from 6 men and 4 women such that the committee has at least 2 women. The number of ways to form such a committee is:
Q2 · Counting Principles · EASY
How many 4-digit numbers contain exactly two distinct digits?