JEE Main20238 Apr 2023Morning ShiftMathematicsSets and RelationsActual
Let the number of elements in sets A and B be five and two respectively. Then the number of subsets of A × B each having at least 3 and at most 6 elements is
Options
- A752
- B782
- C792
- D772
Correct answer
C. 792
Step-by-step solution
Given, The number of elements in sets A and B be five and two respectively, So, n ( A ) = 5 and n ( B ) = 2 Now Cartesian product will be, n A × B = 10 Number of subsets having three elements = 10 C 3 Number of subsets having four elements = 10 C 4 Number of subsets having five elements = 10 C 5 Number of subsets having six elements = 10 C 6 So, number of subsets having atleast 3 and at most 6 elements will be = 10 C 3 + 10 C 4 + 10 C 5 + 10 C 6 = 120 + 210 + 252 + 210 = 792