the total number of ways of selecting two number from the set {1,2,3,4,…..3n} so that their sum divisible by 3 is equal to -

The total number of ways of selecting two numbers from the set {1,2,3,4,........3n} so that their sum is divisible by 3 is equal to a.(2n^(2)-n)/(2) b.(3n^(2)-n)/(2) c.2n^(2)-n d.3n^(2)-n

Total number of ways of selecting two numbers from the set {1,2,3,...,90} so that their sum is divisible by 3, is

If the total number of ways of selecting two numbers from the set {1, 2, 3, ……….., 89, 90} such that their sum is divisible by 3 is k, then (k)/(500) is

The number of ways of selecting 4 numbers from the set S={1,2,3,4,5,6,7,8,9} such that they are not consecutive,is

The number of ways of selecting two numbers from the set {1,2,……………12} whose sun is divisible by 3 is (A) 66 (B) 16 (C) 6 (D) 22

The number of ways of selecting two distinct numbers from the first 15 natural numbers such that their sum is a multiple of 5, is equal to

Two numbers a and b are chosen at random from the set {1,2,3,..,3n}. The probability that a^(3)+b^(3) is divisible by 3, is

The total number of onto functions from the set {1,2,3,4) to the set (3,4,7) is