Odd man out





Odd man out also one of the topics in SAT exam and other competitive exams in which question are asked.Along with this , question are also asked from the topic which is "missing numbers". Students those who are having interest to improve their aptitude skill also have to learn this topic odd-man-out.
Once the students are clear with the concepts and ideas of this topic , they can do any type of problems in this topic .


Concept: In this topic , a sequence of numbers will be given. Among the numbers in the sequence, one particular umber will be different from others either by operation or properties of nos.


Examples:


Find the odd man out.


(a) 3, 5, 7, 12, 17, 19

Answer = 12

Reason : Each of the numbers is prime except 12



(b) 10, 14, 16, 18, 21, 24, 26

Answer = 21
Reason : Each of the numbers is even except 21



(c) 3, 5, 9, 11, 14, 17, 21

Answer = 14
Reason : Each of the numbers is an odd except 14



(d) 1, 4, 9, 16, 23, 25, 36

Answer = 23
Reason : The first number is nothing but the 1 power 2, the second number is 2 power 2 and so on . In this way, fifth number must be 5 power 2 which is 25. But we are having 23



(e) 6, 9, 15, 21, 24, 28, 30


Answer = 28
Reason : Each of the number is a multiple of 3 except 28.



These are few examples on odd-man-out.



odd man out odd man out odd man out
Find the wrong number in each sequence:


(a) 22, 33, 66, 99, 121, 279, 594

Answer = 279

Reason : Each of the number is a multiple of 11 except 279



(b) 36, 27, 18, 13.5, 16,12,20,14

Answer = 14
Reason : The first number has been multiplied by 1.5 and divided by2 in order to get the second number. The third number 18 has been multiplied by 1.5 and divided by 2 in order to get the fourth number 13.5. Here the pattern is , the number is multiplied by 1.5 and divided by 2 in order to generate the number which is coming next. As of this , we must have 15 after 20. But we are having 14. So 14 is the answer.



(c) 1, 8, 27, 64, 124, 216, 343

Answer = 124
Reason : The first number is nothing but 1 to the power 3. The second number is nothing but 2 power 3. In the same way , the fifth number must be the 5 to the power 3 which is 125. But we are having 124.



(d) 5, 16, 6, 16, 7, 16, 9

Answer = 9
Reason, we are having the numbers 5, 6, 7 in the pattern of (n+1) alternatively.In the same way, the number which is next to 7, 16 should be be 8. But we are having 9.



(e) 52, 51, 48, 43, 34, 27, 16

Answer =34.
Reason:In the sequence, the first number is reduced by 1 to get the second number is reduced by 3 to get the third number. That is the numbers are reduced in the order 1, 3, 5, 7........ But, the number 34 in the sequence is not in this pattern. Instead of 34 , we must have 36. So, the wrong number in the sequence is 34.





Find out the missing number in each sequence:


(a) 4, -8, 16, -32, 64, ____

Answer = -128

Reason : Each no. is multiplied by -2 to generate the next number. So, after 64, the next number is -128.



(b) 7, 14, 28, 56, 112, 224, 448, __________

Answer = 122
Reason : The first number has been multiplied by 2 in order to get the second number., The third number has been multiplied by 2 to get the fourth number. In this manner, to get the number next to 448, we have to multiply 448 by2. So we will get 896.



(c) 4, 7, 12, 19, 28, 39, 52, 67, _______

Answer = 84
Reason : The first number is nothing but 1 to the power 2 and added to 3 , the second number is nothing but 2 to the power 2 and added to 3. In the same way, the number right after 67 must be 9 to the power 2 and added to 3 which is 84



(d) 31, 37, 41, 43, 47, 53, _______

Answer = 59
Reason : In the given numbers, all of them are prime. In that manner, the number right after 37 must also be a prime number which is 59.



(e) 2, 4, 12, 48, 240, _______

Answer : 1440
Reason:The first number has been multiplied by 2 in order to get the next number, second number has been multiplied by 3 in order to get the third number. In the same way, 240 has to be multiplied by 6. If it is done so , we would have 240 x 6 = 1440.






odd man out





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