Back to Class XI Mathematics
Class XI Mathematics

Chapter 1: Sets

Standard NCERT & CBSE aligned study curriculum. Master concepts, track accuracy, revise weak areas, and challenge yourself with 9 customized practice modes.

Example 1

Union of Sets Cardinality

In a class of 50 students, 30 play cricket, 25 play football, and 10 play both. How many play either cricket or football?
UABA ∩ B (Shaded)

Calculation Steps:

  1. 1Let A = cricket, B = football.
  2. 2Given: n(A) = 30, n(B) = 25, n(A ∩ B) = 10.
  3. 3Apply formula: n(A ∪ B) = n(A) + n(B) - n(A ∩ B).
  4. 4Calculation: 30 + 25 - 10 = 45 students.
Solution45