Find the odd man out :
- 331, 482, 551, 263, 383, 362, 284
(a) 263 (b) 383 (c) 331 (d) 551 - 835, 734, 642, 751, 853, 981, 532
(a) 751 (b) 853 (c) 981 (d) 532 - 41, 43, 47, 53, 61, 71, 73, 81
(a) 61 (b) 71 (c) 73 (d) 81 - 3, 5, 7, 12, 17, 19
(a) 19 (b) 17 (c) 5 (d) 12 - 16, 25, 36, 72, 144, 196, 225
(a) 36 (b) 72 (c) 196 (d) 225
- (b) 383
Explanation:-
331 = 3 x 1 = 3, 482 = 4 x 2 = 8, 551 = 5 x 1 = 5, 263 = 2 x 3 = 6, 383 = 3 x 3 = 9 So, this number is odd.
362 = 3 x 2 = 6, 284 = 2 x 4 = 8.
In each number except 383, the product of first and third digits is the middle one.
Then, the odd number is (b) 383.Hence, the correct answer is option (b) 383.
- (a) 751
Explanation:-
Sum of the digits of 751 = 7 + 5 + 1 = 13 which is a odd number but rest the sum of digits of all numbers are –
835 = 8 + 3 + 5 = 16, 734 = 7 + 3 + 4 = 14, 642 = 6 + 4 + 2 = 12 , 853 = 8 + 5 + 3 = 16.
These are even number. So, the odd number is 751.Hence, the correct answer is option (a) 751.
- (d) 81
Explanation:-
The sum of the digits of all numbers are –
41 = 4 + 1 = 5, 43 = 4 + 3 = 7, 47 = 4 + 7 = 11, 53 = 5 + 3 = 8, 61 = 6 + 1 = 7, 73 = 7 + 3 = 10, 81 = 8 + 1 = 9 .
Here, 81 is perfect square of 9 and sum of their digits is a perfect square of 3.
So, the odd number is 81.Hence, the correct answer is option (d) 81.
- (d) 12
Explanation:-
12 is an even number but rest are the odd numbers.Then, the odd number if 12.
Hence, the correct answer is option (d) 12.
- (b) 72
Explanation:-
72 is not a perfect square of any number but rest are the perfect square of the numbers.
16 is the square of 5,
25 is the square if 5,
36 is the square of 6,
144 is the square of 12,
196 is the square of 14 ,
And 225 is the square of 15.Then, the odd number is 72.
Hence, the correct answer is option (b) 72.