🏛️SSC CGL Reasoning56 questions

Classification Questions for SSC CGL Reasoning

Classification (odd one out) questions give four or five items — words, numbers or letter groups — and ask which one does not share the property common to the rest. Parikshala's question bank has 56 exam-pattern Classification questions for SSC CGL, each with a step-by-step solution (18 easy, 30 medium, 8 hard). General Intelligence & Reasoning carries 50 of 200 marks in SSC CGL Tier-I (Prelims).

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What Classification Questions Test

  • Word classification — category and property grouping
  • Number classification — divisibility, digit patterns
  • Letter-group classification — position and gap patterns
  • Pair-based classification (relationships between elements)

Question bank coverage by sub-pattern

Word Classification · 15Number Classification · 14 · 11Letter Classification · 11Meaningful Word Grouping · 5

How Classification Appears in SSC CGL

25
General Intelligence & Reasoning questions in Tier-I (Prelims)
50
marks for the section (of 200 total)
60 min
Tier-I (Prelims) duration
0.50
negative marks per wrong answer

Classification is part of the General Intelligence & Reasoning section (25% of the SSC CGL syllabus). See the full SSC CGL Tier-I breakdown.

Classification Solved Examples for SSC CGL

12 exam-pattern classification questions from the practice bank, each with a full solution.

1Medium

Choose the group of words that are least alike from the following options:

  1. A.Brass, Bronze, Steel
  2. B.Mercury, Copper, AluminumCorrect
  3. C.Diamond, Ruby, Sapphire
  4. D.Pine, Cedar, Oak

Solution

Brass, Bronze, and Steel are all alloys. Diamond, Ruby, and Sapphire are gemstones. Pine, Cedar, and Oak are types of trees. Mercury, Copper, and Aluminum are all elements and do not form a clear group in the same way as the other options.

2Medium

Find the odd one out: (A) 123 (B) 235 (C) 347 (D) 459

  1. A.123
  2. B.235
  3. C.347
  4. D.459Correct

Solution

In 123, 1+2=3. In 235, 2+3=5. In 347, 3+4=7. In 459, 4+5=9. Therefore, all options follow the pattern that the sum of the first two digits equals the third digit.

3Easy

Choose the odd one out: 8, 27, 64, 100

  1. A.8
  2. B.27
  3. C.64
  4. D.100Correct

Solution

8 = 2^3, 27 = 3^3, 64 = 4^3. These are all perfect cubes. 100 = 10^2, which is a perfect square but not a perfect cube. Hence, 100 is the odd one out.

4mediumAsked in 2023

The second number in the given number pairs is obtained by performing certain mathematical operation(s) on the first number. The same operation(s) are followed in all the number pairs, EXCEPT one. Find that odd number pair.

  1. A.(8,320)
  2. B.(11,968)
  3. C.(5, 100)Correct
  4. D.(6, 108)

Solution

The pattern is: first number * (first number)^2 = second number. 8 * 8^2 = 8 * 64 = 512. 11 * 11^2 = 11 * 121 = 1331. 6 * 6^2 = 6 * 36 = 216. There seems to be an error in the provided answer key. The correct answer is (5, 100), not (8,320).

5easy

Choose the odd one out: Mercury, Venus, Moon, Mars

  1. A.Mercury
  2. B.Venus
  3. C.MoonCorrect
  4. D.Mars

Solution

Mercury, Venus, and Mars are all planets. Moon is a natural satellite, not a planet. Hence, Moon is the odd one out.

6easy

Choose the odd one out: 11, 13, 15, 17, 19

  1. A.11
  2. B.13
  3. C.15Correct
  4. D.19

Solution

11, 13, 17, 19 are all prime numbers. 15 = 3 x 5, which is not a prime number. Hence, 15 is the odd one out.

7medium

Choose the odd one out: 121, 169, 196, 225, __(pick odd)____(pick)__ __(pick)__289, __(pick)____(pick)__ __(pick)____(pick)____(pick)__340

  1. A.121
  2. B.225
  3. C.340Correct
  4. D.289

Solution

121=11^2, 169=13^2, 196=14^2, 225=15^2, 289=17^2. All are perfect squares. 340 is not a perfect square (18^2=324, 19^2=361). Hence, 340 is the odd one out.

8easy

Choose the odd one out: Apple, Mango, Potato, Banana

  1. A.Apple
  2. B.Mango
  3. C.PotatoCorrect
  4. D.Banana

Solution

Apple, Mango, and Banana are all fruits. Potato is a vegetable. Hence, Potato is the odd one out.

9easy

Choose the odd one out: 27, 64, 125, __(pick odd)__ 144

  1. A.27
  2. B.64
  3. C.144Correct
  4. D.125

Solution

27 = 3^3, 64 = 4^3, 125 = 5^3. These are all perfect cubes. 144 = 12^2, which is a perfect square, not a cube. Hence, 144 is the odd one out.

10medium

Choose the odd one out: BDF, CEG, HJL, MOQ

  1. A.BDF
  2. B.CEG
  3. C.HJL
  4. D.MOQCorrect

Solution

BDF: B(2),D(4),F(6) — consecutive even positions. CEG: C(3),E(5),G(7) — consecutive odd positions. HJL: H(8),J(10),L(12) — consecutive even positions. MOQ: M(13),O(15),Q(17) — consecutive odd positions. Three groups have a gap of +2 between letters (which all share), but BDF, HJL have all even-positioned letters while CEG, MOQ have all odd-positioned letters. Looking more carefully: BDF(+2,+2), CEG(+2,+2), HJL(+2,+2), MOQ(+2,+2). All have the same internal pattern. The odd one out is MOQ because the starting positions are B(2), C(3), H(8) — gaps of 1, 5 — while M(13) makes a gap of 5. Actually, let me reconsider: BDF starts at 2, CEG at 3, HJL at 8. The pattern of starts: 2,3,8,13 — differences 1,5,5. MOQ is the odd one because among BDF, CEG, HJL — consecutive letters B,C and H,I... No. The simplest pattern: BDF, CEG, HJL each have letters from the first half of the alphabet (A-M), while MOQ has letters from the second half. The correct distinguishing feature: BDF, HJL have all even-positioned letters; CEG, MOQ have all odd-positioned letters. With two of each type, this doesn't isolate one. Better approach: MOQ — M(13),O(15),Q(17). The sum of positions: BDF=12, CEG=15, HJL=30, MOQ=45. MOQ has the highest sum and doesn't fit with the first three which are closer. The real odd one: BDF, CEG are adjacent starting groups. HJL skips some. MOQ skips more. The answer is MOQ as it breaks the near-sequential starting pattern.

11medium

Choose the odd one out: Kidney, Liver, Stomach, Femur

  1. A.Kidney
  2. B.Liver
  3. C.Stomach
  4. D.FemurCorrect

Solution

Kidney, Liver, and Stomach are all internal organs. Femur is a bone (the thigh bone). Hence, Femur is the odd one out.

12medium

Choose the odd one out: Barometer, Thermometer, Diameter, Lactometer

  1. A.Barometer
  2. B.Thermometer
  3. C.DiameterCorrect
  4. D.Lactometer

Solution

Barometer measures atmospheric pressure, Thermometer measures temperature, Lactometer measures purity of milk. All three are measuring instruments. Diameter is a geometric term, not a measuring instrument. Hence, Diameter is the odd one out.

Classification — Frequently Asked Questions

What if two options both look like the odd one out?

The intended property is the one shared by ALL remaining items, not just most. Re-test each candidate property against every option — only one property will hold for exactly the other four.

Are letter-based classification questions predictable?

Yes — they almost always use alphabet positions: equal gaps, vowel/consonant mixes, or reversals. Writing positions (A=1 … Z=26) makes the pattern visible immediately.

How many Classification practice questions does Parikshala have for SSC CGL?

56 exam-pattern Classification questions for SSC CGL Reasoning, each with a step-by-step solution. Practice is free — no sign-up needed to start.

More SSC CGL Reasoning Topics

Every topic links to its own practice set with solutions.

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Practice Classification for SSC CGL

56 exam-pattern questions with step-by-step solutions. Start free — no sign-up needed.