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 Number Series — practice questions
Explore 42 free Number Series questions in RRB Group D Reasoning. Open each question or exercise to read its content, reference answers and available explanation.
Practise Number Series with Quill →Number Series questions and exercises with answers
Showing questions 1–30 of 42.
5 : 24 :: 8 : ?Read the answer and worked solution →Find the next number in the series: 26, 29, 33, 38, _____.Read the answer and worked solution →Find the next number in the series: 1200, 600, 300, _____.Read the answer and worked solution →Select the missing number to complete the series: 59967, 59964, 59961, 59958, _____.Read the answer and worked solution →Match each proposition form to its letterRead the answer and worked solution →Universal or particular? Affirmative or negative?Read the answer and worked solution →Affirmative or negative?Read the answer and worked solution →Naming the formRead the answer and worked solution →True or false: what conversion allowsRead the answer and worked solution →Tap every inference that is actually validRead the answer and worked solution →Complete the four formsRead the answer and worked solution →True or false: what a universal claim coversRead the answer and worked solution →Deduction or induction?Read the answer and worked solution →Order the steps: test a syllogismRead the answer and worked solution →True or false: reasoning from two premisesRead the answer and worked solution →Assertion and reasonRead the answer and worked solution →Two are true, one is notRead the answer and worked solution →Three of these are wrong. Find the one that holds.Read the answer and worked solution →Flip and pair: letter with statementRead the answer and worked solution →Spot the one that does not belongRead the answer and worked solution →Deduction against inductionRead the answer and worked solution →Tap every statement that follows from 'All cats are animals'Read the answer and worked solution →Complete the conversion ruleRead the answer and worked solution →Which reversal is safe?Read the answer and worked solution →Complete the definition of a sequenceRead the answer and worked solution →Sequence or series?Read the answer and worked solution →True or false: sequences and seriesRead the answer and worked solution →Complete the geometric progression ruleRead the answer and worked solution →Spotting the ruleRead the answer and worked solution →Constant difference, or constant ratio?Read the answer and worked solution →
Worked practice questions
Find the next number in the series: 26, 29, 33, 38, _____.
- 42
- 44
- 50
- 54
Show answer and solution
Correct answer: B. 44
1. Differences: 29−26 = 3, 33−29 = 4, 38−33 = 5.
2. The differences increase by 1 each time, so the next difference is 6.
3. Next term = 38 + 6 = 44.
_Source: RRB Group D CEN-02/2018 PYQ, Q.11._
Find the next number in the series: 1200, 600, 300, _____.
- 150
- 75
- 250
- 500
Show answer and solution
Correct answer: A. 150
1. Each term is half the previous: 1200 ÷ 2 = 600, 600 ÷ 2 = 300.
2. Next term = 300 ÷ 2.
3. = 150.
_Source: RRB Group D CEN-02/2018 PYQ, Q.32._
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