Classification

Classification is the process of grouping similar things together. In SSC CGL Reasoning, classification questions give you four options and you have to find the one that is different from the rest. This topic is also called Odd One Out.

Types of Classification in SSC CGL:

1. Word Classification Four words are given and you have to find the one that does not belong to the same group.

Example: 

Which is the odd one out - Mango, Banana, Potato, Apple? 

Answer: Potato 

(Mango, Banana and Apple are fruits. Potato is a vegetable.)

2. Number Classification Four numbers are given and you have to find the odd one out based on a mathematical property.

Example: Which is the odd one out - 16, 25, 36, 45? 

Answer: 45 

(16, 25 and 36 are perfect squares. 45 is not a perfect square.)

3. Letter Classification Four groups of letters are given and you have to find the odd one out.

Example: 

Which is the odd one out - AZ, BY, CX, DE? 

Answer: DE 

(AZ, BY and CX are pairs of letters that are opposite in the alphabet. D and E are consecutive letters.)

4. Miscellaneous Classification Questions based on general knowledge like countries and capitals, animals and their class, sports and equipment etc.

Example: 

Which is the odd one out - Cricket, Football, Chess, Hockey?

 Answer: Chess 

(Cricket, Football and Hockey are outdoor sports. Chess is an indoor board game.)

How to Solve Classification Questions:

Step 1 - Read all four options carefully. 

Step 2 - Find a common property among three of them. 

Step 3 - The one that does not share that property is the odd one out. 

Step 4 - Always look for the most specific common property - do not go with a very broad category. 

Step 5 - In number classification, check for squares, cubes, primes, even, odd and multiples.

Common Categories Used in Word Classification:

• Fruits, Vegetables, Animals, Birds, Insects
• Countries, Capitals, Currencies, Languages
• Sports, Musical Instruments, Professions
• Parts of body, Planets, Rivers, Mountains
• Prime numbers, Perfect squares, Even/Odd numbers

Common Mistakes to Avoid:

• Do not pick an answer too quickly - sometimes two options seem odd but only one is correct
• In number classification, check multiple properties before deciding
• Do not rely only on general knowledge - use logical elimination

Important Tips:

• Always define the group first before finding the odd one
• Practice with at least 5 different categories daily
• In exam, if confused between two options, go with the most specific relationship