## Series Completion: General Intelligence or Reasoning MCQ Question with Answer

This chapter deals with questions in which series of numbers or alphabetical letters are given, which are generally called as terms of the series. These terms follow a certain pattern throughout. The candidate is required to recognize this pattern and either complete the given series with the most suitable alternative or find the wrong term in the series.

Quiz-1 | Quiz-2 | Quiz-3 | Quiz-4 | Quiz-5 |

Direction: What should come in place of question mark (?) in the following number series?

Q11. 4, 6, 12, 14, 28, 30, ?

(a) 32

(b) 40

(c) 50

(d) 60

Answer: (d) Explanation: The given series is +2, ×2, +2, ×2, … ∴ missing number = 30 × 2 = 60 |

Q12. 8, 28, 116, 584, ?

(a) 1752

(b) 3502

(c) 3504

(d) 3508

(e) None of these

Answer: (c) Solution: The given series is in the pattern: × 3 + 4, × 4 + 4, × 5 + 4, ….. (8 × 3) + 4 = 28; (28 × 4) + 4 = 116; (116 × 5) + 4 = 584 ; (584 × 6) + 4 = 3508 So, the missing term is 584 × 6 + 4 = 3508. |

Q12. 3 4 10 33 136 685 ?

(a) 3430

(b) 4802

(c) 5145

(d) 4116

(e) 5488

Answer: (d) Solution: In this particular Series, the pattern is- 3 × 1 + 1 = 4; 4 × 2 + 2 = 10; 10 × 3 + 3 = 33; 33 × 4 + 4 = 136; 136 × 5 + 5 = 685; ∴ missing number = 685 × 6 + 6 = 4116. |

Q13. 1, 9, 25, 49, ?, 121

(a) 64

(b) 81

(c) 91

(d) 100

(e) None of these

Answer: (b) Solution: The given series consists of squares of consecutive odd numbers i.e. 1 So, the missing term = 9 |

Q14. Find the Wrong term of the Series: 69, 55, 26, 13, 5

(a) 69

(b) 55

(c) 26

(d) 13

(e) 5

Answer: (e) Solution: We found that the series contains each term is one more than the product of the digits of the preceding term. Thus (6 × 9 ) + 1 = 55, (5 × 5) + 1 = 26, (2 × 6 ) + 1 = 13, (1 × 3) + 1 = 4. Hence option (e). |

Q15. 2, 7, 17, 32, ..?…….

(a) 42

(b) 52

(c) 47

(d) 27

(e) 62

Answer: (b) Solution: In this particular series the gap between the numbers are 5, 10, 15, …so the next difference must be 20. Than the next number be 32 + 20 = 52. |

Q16. 105, 94.5, 103.95, 93.56, ..?…

(a) 102.91

(b) 102.98

(c) 102.95

(d) 103. 91

(e) none of these

Answer: (a) Solution: In this particular Series the numbers are arranged on percentage increase and decrease pattern. As first there is 10% decrease and than 10% increase..i.e. 105 – 10% of 105 = 94.5, 94.5 + 10% of 94.5 = 103.95 ..and so on. Than the next number = 93.56 + 10% of 93.56 = 102.916 |

Q17. 51975, 9450, 2100, 600, 240, 160 ?

(a) 80

(b) 120

(c) 320

(d) 240

(e) 300

Answer: (c) Solution: The given series is following pattern: ÷5.5, ÷4.5, ÷3.5, ÷2.5, ÷1.5, ÷0.5 Than the next number = 160 ÷ 0.5 = 320 |

Q18. 16, 12, 18, 40.5, 121.5, 455.625 ?

(a) 2050.1125

(b) 2050.2125

(c) 2050.3125

(d) 2050.4125

(e) 2050.5125

Answer: (e) Solution: The pattern of the above Series: 16 × 0.75 = 12, 12 ×2 × 0.75 = 18, 18 × 3 × 0.75 = 40.5, 40.5 × 4 × 0.75 = 121.5, ……, Than the next number = 455.625 × 6 × 0.75 = 2050.3125. |

Q19. 6, 11, 21, 36, 56, (? )

(a) 42

(b) 51

(c) 81

(d) 91

Answer: (c) Solution: In this particular series the gap between the numbers are 5, 10, 15, …so the next difference must be 25. Than the next number be 56 +25 = 81 |

Q20. Which term of the series 5, 10, 20, 40, … is 1280 ?

(a) 10th

(b) 9th

(c) 8th

(d) None of these

Answer: (b) Solution: Clearly. 5 x 2 = 10, 10 x 2 = 20, 20 x 2 – 40,… P So. the series is a G.P. in which First term ( a) = 5 and Common ratio (r) = 2. Let the number of terms be n. Then, 5 x 2 ⇒2 ⇒n – 1 = 8 or n = 9. |