ICSE Class 10 Mathematics: Probability and Statistics — Important Questions with Answers 2026

Short Answer Questions (2-3 Marks)

• Q: A bag contains 5 red, 3 blue, and 2 green balls. One ball is drawn at random. Find: (i) P(red), (ii) P(not green), (iii) P(blue or green).
  Ans: Total balls = 5 + 3 + 2 = 10. (i) P(red) = 5/10 = 1/2. (ii) P(not green) = 1 - P(green) = 1 - 2/10 = 8/10 = 4/5. (iii) P(blue or green) = (3+2)/10 = 5/10 = 1/2.
• Q: Two dice are thrown simultaneously. Find the probability of getting: (i) a sum of 7, (ii) a doublet.
  Ans: Total outcomes = 6 × 6 = 36. (i) Sum of 7: (1,6),(2,5),(3,4),(4,3),(5,2),(6,1) = 6 outcomes. P = 6/36 = 1/6. (ii) Doublets: (1,1),(2,2),(3,3),(4,4),(5,5),(6,6) = 6 outcomes. P = 6/36 = 1/6.
• Q: Find the mean of the following data: 12, 15, 18, 20, 25, 30.
  Ans: Mean = Sum of observations / Number of observations = (12+15+18+20+25+30)/6 = 120/6 = 20.

Long Answer / Application Questions (4-6 Marks)

• Q: Find the median of: 3, 7, 2, 9, 5, 11, 4.
  Ans: Arrange in ascending order: 2, 3, 4, 5, 7, 9, 11. n = 7 (odd). Median = ((n+1)/2)th value = 4th value = 5.

Exam Tips for This Chapter

• Revise all definitions and laws from Probability and Statistics — they are commonly asked as 1-2 mark questions
• Practice diagrams related to Probability and Statistics — neat labelled diagrams carry 2-3 marks
• For numericals, always show formula → substitution → answer with correct units
• Previous year analysis shows Probability and Statistics carries 8-12 marks in the board exam