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IBPS RRB Office Assistant Number Series — practice questions

Explore 4 free Number Series questions in IBPS RRB Office Assistant Quantitative Aptitude. Open each question or exercise to read its content, reference answers and available explanation.

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Number Series questions and exercises with answers

Showing questions 1–4 of 4.

Find the missing term: 100, 100, 50, 12.5, ?Read the answer and worked solution →Find the missing term: 1023, 987, 915, 807, ?Read the answer and worked solution →Find the missing term: 8, 9, 15, 32, ?, 250.5Read the answer and worked solution →Find the missing term: 12, 20, 34, 57, ?Read the answer and worked solution →

Worked practice questions

Find the missing term: 100, 100, 50, 12.5, ?

  1. 2.5625
  2. 3.5625
  3. 1.5625
  4. 0.5625
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Correct answer: C. 1.5625

1. The multipliers halve each step: ×1, ×0.5, ×0.25, ×0.125. 2. 100×1 = 100; 100×0.5 = 50; 50×0.25 = 12.5. 3. Next: 12.5 × 0.125 = **1.5625**. _Source: IBPS RRB Officer Scale I Prelims PYQ (Examrace), Q.73_

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Find the missing term: 1023, 987, 915, 807, ?

  1. 636
  2. 663
  3. 543
  4. 632
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Correct answer: B. 663

1. Differences: 1023 − 987 = 36; 987 − 915 = 72; 915 − 807 = 108. 2. The subtracted values are 36, 72, 108 — multiples of 36, so the next is 144. 3. 807 − 144 = **663**. _Source: IBPS RRB Officer Scale I Prelims PYQ (Examrace), Q.75_

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Find the missing term: 8, 9, 15, 32, ?, 250.5

  1. 62.5
  2. 47.5
  3. 82.5
  4. 64.5
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Correct answer: C. 82.5

1. The pattern is ×1+1, ×1.5+1.5, ×2+2, ×2.5+2.5, … 2. 8×1+1 = 9; 9×1.5+1.5 = 15; 15×2+2 = 32. 3. Next: 32 × 2.5 + 2.5 = **82.5** (and 82.5 × 3 + 3 = 250.5 confirms it). _Source: IBPS RRB Officer Scale I Prelims PYQ (Examrace), Q.71_

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More Quantitative Aptitude topics

Square RootsSimple InterestMensurationPercentagesShortcutsSimple & Compound InterestSquares And RootsMultiplication