JEE Main202226 Jul 2022Evening ShiftMathematicsSets and RelationsActual
Let A = 1 , 2 , 3 , 4 , 5 , 6 , 7 and B = 3 , 6 , 7 , 9 . Then the number of elements in the set C ⊆ A : C ∩ B ≠ ϕ is ______
Correct answer
0
Step-by-step solution
Given, A = 1 , 2 , 3 , 4 , 5 , 6 , 7 and B = 3 , 6 , 7 , 9 We know that if any set has n elements then total number of subset is given by 2 n So, total subset of A = 2 7 = 128 C ∩ B = ϕ when set C contains the element 1 , 2 , 4 , 5 ∴     S = C ⊆ A ; C ∩ B ≠ ϕ = Total - C ∩ B = ϕ = 128 - 2 4 = 128 - 16 = 112