alleryStart learning →5 : 24 :: 8 : ?
- 81
- 63
- 48
- 56
Show answer and solution
Correct answer: B. 63
Pattern: n² - 1. 5² - 1 = 24. 8² - 1 = 63.
RRB Group D Series Coding Relations — practice questions
Explore 10 free Series Coding Relations questions in RRB Group D Reasoning. Open each question or exercise to read its content, reference answers and available explanation.
Practise Series Coding Relations with Quill →Series Coding Relations questions and exercises with answers
Showing questions 1–10 of 10.
5 : 24 :: 8 : ?Read the answer and worked solution →Find the next term: 2, 6, 12, 20, 30, ?Read the answer and worked solution →Catch the G.P.sRead the answer and worked solution →Pop the sequence makersRead the answer and worked solution →Steer into the G.P. laneRead the answer and worked solution →Slice the G.P. wordsRead the answer and worked solution →A.M. or G.M.Read the answer and worked solution →Which notation letterRead the answer and worked solution →Type the answerRead the answer and worked solution →G.P. bingoRead the answer and worked solution →
Worked practice questions
Find the next term: 2, 6, 12, 20, 30, ?
- 36
- 40
- 42
- 44
Show answer and solution
Correct answer: C. 42
**Differences:** 4, 6, 8, 10 (increasing by 2).
Next difference = 12. So 30 + 12 = 42. Formula: n(n+1) for n = 1..6.
Catch the G.P.s
Read exercise and reference answers
- Items
- Matches the category
- Yes
- Item
- 2, 4, 8, 16
- Matches the category
- Yes
- Item
- 5, 25, 125
- Matches the category
- Yes
- Item
- 1, 0.01, 0.0001
- Matches the category
- Yes
- Item
- 1, 4, 16, 64
- Matches the category
- Yes
- Item
- Bacteria x2
- Matches the category
- No
- Item
- 1, 3, 5, 7
- Matches the category
- No
- Item
- 2, 3, 5, 7
- Matches the category
- No
- Item
- 1, 1, 2, 3, 5
- Category
- Geometric progression
- Instructions
- Catch the sequences with a constant ratio. Let the others fall.
_Source: syllabus Mathematics, Chapter 8, Sequences and Series._
How to practise
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