Classification

Classification

Classification

Classification means to ‘assort the items of a given group on the basis of a
certain common quality they posses and spot the odd one out’.

In these types of questions we will be provided with a group of 5 items out of
which 4 would be similar to one another in a certain relationship among
themselves and 1 would differ from them. Our answer is the odd item.

2-types of questions can be expected in this topic

  • Alphabetical series
  • Number series

Alphabetical Series:

Five groups of words will be given out of which one group will be different
Hints to solve:

  • Look for the presence of vowels
  • Vowels if present, then the number of vowels in each group should be considered
  •  Check the number of alphabets in between the letters in each group both in normal and reverse direction in the English alphabet series.

Example 1: 

Direction: If English alphabet is written in reverse order then- Which letter is 5th at right of 12 from right?

(a) P
(b) Q
(c) G
(d) W
(e) None of these

Answer: (c) G

Example 2: 

If English alphabet is written in reverse order then- If the 2nd half of an English alphabet is written in reverse order, which letter will be the 5th at left from 21st letter from left?

(a) A
(b) B
(c) X
(d) D
(e) None of these

Answer: (c) X

Example 3: Four of the following five are alike in a certain way and hence form a group. Which one does not belong to the group?

(a) OPQ
(b) ABC
(c) VWG
(d) EFG
(e) None of these

Answer: (c) Each of the options a, b, d u0026amp; e consists of a vowel
OPQ, EFG, ABC, IJK
Therefore, the odd one out of the group is option (c) VWG which consists of
only consonants.

Numerical Series

Here for finding the odd number out of the given numbers we can follow the following order step by step. Check whether the given numbers are
1) Divisible by 3
2) Odd number group
3) Even number group
4) Prime number
5) Square roots
6) Cube roots
7) Square ± number (ex. 92 ± 1)
8) Cube ± number (ex. 93 ± 1)
9) Sum of digits
10)Divisible by 5, 7, 11, 13, 17

Example 4:

In the following question, identify the wrong number in the series.

0, 7, 28, 63, 124, 215

(a) 7
(b) 28
(c) 124
(d) 215
(e) None of these

Answer: (b)

0= 1³ – 1

7 = 2³ – 1

28 = 3³ + 1

63 = 4³ – 1

124 = 5³ – 1

215 = 6³ – 1

Hence, 28 is the wrong number.

Example 5:

Find the wrong term in the following series.

5, 13, 29, 61, 120, 253

(a) 253
(b) 29
(c) 61
(d) 120
(e) None of these

Answer: (d) 120

5 + 8 = 13

13 + 16 = 29

29 + 32 = 61

61 + 64 = 125

125 + 128 = 253

Therefore, 120 is wrong number.

Example 6: 

Choose the correct alternatives from the given ones to complete the series:2, ?, 8, 16, 32

(a) 3
(b) 4
(c) 5
(d) 6
(e) None of these

Answer: (b) 4

The pattern is that every number is the double of the previous number

2,  2 × 2 = 4, 4 × 2 = 8, 8 × 2 = 16, 16 ×2 = 32.

So, (?) = 4