NCERT Mathematics, Class 11, textbook pages 289–313

How to help your child with Class 11 Maths Chapter 14, Probability, at home

Sample spaces, events and axioms of probability, explained for parents: a 45-minute study session, a quick challenge, a 5-day plan and the mistakes to watch for.

3 coins: 8 outcomesP(A ∪ B)= P(A) + P(B) − P(A ∩ B)

NCERT Class 11 Maths Chapter 14 Probability: what it teaches

Your teen describes random experiments with sample spaces, classifies events (mutually exclusive, exhaustive), and uses the axioms and the addition rule to calculate probabilities.

Why it matters later. Probability continues in Class 12 with conditional probability and Bayes’ theorem.

See it: this chapter in pictures

HHH, HHT, HTH, HTTTHH, THT, TTH, TTT8 outcomes
List systematically.
king or heart4 + 13 − 1 = 16P = 16/52 = 4/13
Don’t double-count the king of hearts.
P(E) + P(not E) = 1P(at least one head in 3)= 1 − 1/8 = 7/8
Complements simplify ‘at least’ problems.

You need

  • coins, dice
  • a pack of cards

Tonight’s 45 minutes

  1. Write the sample space for tossing 3 coins (8 outcomes).
  2. Events: A = at least 2 heads, B = exactly 1 head. Mutually exclusive?
  3. Use P(A ∪ B) = P(A) + P(B) − P(A ∩ B) for cards: king or heart (16/52).
  4. Check that all probabilities in a sample space add to 1.

Words to use

  • sample space
  • event
  • mutually exclusive
  • exhaustive
  • complement
  • axiom

Watch for

  • Adding probabilities of overlapping events without subtracting. Use the addition rule.
  • Confusing mutually exclusive with independent. Mutually exclusive events can’t both happen.

What it sounds like at home

A short example of the conversation. Your words will differ; the questions are what matter.

YouKing or heart?

Your child4 + 13 − 1 = 16 cards: 4/13.

A game for this week: Card detective

  1. Define events on a deck.
  2. Predict probabilities.
  3. Draw cards to test.
  4. Compare with theory.

A 5-day plan, 45 minutes a day

  1. Day 1Explain-back.
  2. Day 2Worked examples.
  3. Day 3Practice set.
  4. Day 4Real-life problem.
  5. Day 5Mixed quiz.

Everyday moments to practise

  • Games of chance.
  • Risk assessment.
  • Weather forecasts.
  • Insurance.

Quick check

Ask these at the end of the week. Tap to see the answer.

Sample space size for 3 coins?

8.

P(king or heart)?

4/13.

P(E) + P(not E)?

1.

Ready for the next chapter when your child…

  • Writes sample spaces.
  • Classifies events.
  • Uses the addition rule.

Activities, wording and illustrations are Mathify Kids’ own, following the topics of NCERT’s Mathematics (Class 11). See the full Class 11 parent guide for every chapter.

Questions parents ask

What is a sample space?

The set of all possible outcomes.

What are mutually exclusive events?

Events that cannot occur together.

What is the addition rule?

P(A ∪ B) = P(A) + P(B) − P(A ∩ B).