`S={1,2,3,..... 11}` if 3 numbers are chosen at random from S, the probability for they are in `G.P.`

S={1,2,3,....20} if 3 numbers are chosen at random from S, the probability for they are in A.P.is (A) (3)/(38) (B) (35)/(33) (C) (33)/(35) (D) (1)/(38)

If S={1,2,3,...,20} .If 3 numbers are chosen at random from S. The probability for they are in A.P is I then 38I-1 is

If S={1,2,3,...,20} .If 3 numbers are chosen at random from S .The probability for they are in A.P is I then 38I-1 is

Three numbers are chosen at random from 1 to 15. The probability that they are consecutive is

Three numbers are chosen at random from 1 to 20 .The probability that they are consecutive is

Let S = {1, 2, 3, ..., 100). Suppose b and c are chosen at random from the set S. The probability that 4x^2+bx+c has equal roots is

Four numbers are chosen at random from (1,2,3,…..40) . The probability that they are not consecutive is

Four numbers are chosen at random from {1,2,3,......,40}. The probability that they are not consecutive is

Four numbers are chosen at random from {1,2,3,......, 40} . The probability that they are not consecutive is

From the set {1,2,3,4,5} two numbers a and b (a != b) are chosen at random . The probability that a/b is an integar is