Kohli and his Magic Ball

Virat Kohli knows RCB's batting very well, he knows that team will not chase the target if the target is $K$ or more than $K$. Kohli has got a magic ball by which he can restrict the opposition team's total runs. But this magic ball has rules of its own. Kohli has to choose some elements from array to make it possible, more the number of elements chosen, more the probability of magic ball workin