1) 2nN = (2n)! 2)N(n!) = (1.3.5…(2n-1)) 3) N = 2nCn 4) None of these Answer: (1) 2nN = (2n)! Number of ways, N = (2nC2) (2n-2C2) …….... View Article
1) 18 2) 27 3) 45 4) 56 Answer: (2) 27 Solution: Number of ways when we can get the sum of score of 11 by tossing three dices: (1,6,4) =... View Article
1) 17 2) 51 3) 18 4) 35 Answer: n=18 Solution: In chess, there are two players. Total number of games played = 153 Therefore, nC2 = 153... View Article
1) 270 2) 220 3) 282 4) 342 Answer: (4) 342 Solution: Given, 3,4,5 and 6 points are marked on the sides AB,BC,CD and DA respectively. To... View Article
1) n(nr-1)/(n-1) 2) (nr-1)/(n-1) 3) n(rn-1)/(n-1) 4) n(n-r)/(n-1) Answer: (1) n(nr-1)/(n-1) Solution: Total number of things given = n If... View Article
1) 2 x 12! 2) 24 3) 2 x 15! 4) 2! x 13! Answer: (1) 2 x 12! Solution: Sittings for secretary, principal and deputy secretary are fixed.... View Article
1) 250 2) 252 3) 254 4) 256 Answer: (4) 256 Solution: Prime factorisation of 770 = 2 x 5 x 7 x 11 Each of the four prime factors can be... View Article
1) 55 2) 66 3) 77 4) 88 Answer: (3) 77 Solution: Using the digits 1,2 and 3, we can divide the number 10 in two ways: {3,2,1,1,1,1,1} and... View Article