From the set of numbers s={1, 2, 3, 4}, how many minimum numbers must be selected to guarantee that at least one pair of these numbers has a sum equal to 7?
Shouldn’t answer be 4 since the set s {1,2,3,4} itself satisfies.
Even {3,4} would be satistifying isn’t ?
to ensure that a pair has sum 7
the possible pair is 3,4
so if u select 1,2,3 then only if u next select 4 only then will a pair be generated such that sum is 7
so 4 is the answer ( 4 digits needs to be min chosen to get sum 7)
So, the correct answer should be 2 but from the given options (5, 7, 4, 14) answer should be 4 but the answer given is 5. Then why is it so?
yes must be some mistake