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TNPSC: Number & alphabet series — practice questions

Logical Reasoning & Mental Ability · Group 2 & 2A · தமிழ் & English

5 questions Day 31 of the 60-day Group 2 plan

Number & alphabet series is part of Logical Reasoning & Mental Ability in the TNPSC syllabus (Group 2 & 2A). The questions below are free, bilingual (தமிழ் & English) and each one has a full explanation. For a structured path, this topic is Day 31 of the free 60-day TNPSC study plan.

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Q1. Find the next term in the series: 2, 6, 12, 20, 30, ?

A. 4040 B. 3636 C. 4444 D. 4242
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Answer: D. 42 · 42
The differences are 4, 6, 8, 10, 12; adding 12 to 30 gives 42.

Q2. What comes next: 3, 6, 12, 24, ?

A. 4242 B. 4444 C. 4848 D. 5050
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Answer: C. 48 · 48
Each term is double the previous one: 24 x 2 = 48.

Q3. Find the missing number: 1, 4, 9, 16, 25, ?

A. 3030 B. 3535 C. 4949 D. 3636
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Answer: D. 36 · 36
These are perfect squares; 6 squared = 36.

Q4. Complete the letter series: A, C, E, G, ?

A. HH B. II C. JJ D. KK
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Answer: B. I · I
Each letter advances by two positions: G + 2 = I.

Q5. Find the next term: 5, 11, 23, 47, ?

A. 9393 B. 9494 C. 9595 D. 9696
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Answer: C. 95 · 95
Each term is the previous term times 2 plus 1: 47 x 2 + 1 = 95.
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