KVPY2016MathematicsSets and Relations
Let A₁, A₂ , A_ m be non-empty subsets of 1,2,3, , 100 satisfying the following conditions: (1) the numbers | A ₁ |, | A ₂ |, , | A _ m | are distinct; (2) A ₁, ~A ₂, , A _ m are pairwise disjoint. (Here A denotes the number of elements in the set A .) Then the maximum possible value of m is
Options
- A13
- B14
- C15
- D16
Correct answer
A. 13
Step-by-step solution
The possibility is array l | A ₁ |=1 ; | A ₂ |=2 ; | A ₃ |=3 ; ., | A _ m |= m 1+2+3+ + m 100 Because all are disjoint m ( m +1) 2 100 m < 14 array 14^ th set will have the same size as that of one of the previous sets So, m =13