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CDS Average Questions with Answers & Explanations

18 Average questions from the Elementary Mathematics section of CDS, each with the correct answer and a worked explanation. Try each question first, then tap Show answer to check. When you're ready, take the timed chapter-wise test to see your all-India rank.

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Question 1

The average of 6 numbers is 54. If one number is removed, the average of the remaining numbers becomes 58. What is the number removed?

  1. A33
  2. B34
  3. C35
  4. D36
Show answer
Answer: (B) 34 Removed number = 6 × 54 − 5 × 58 = 34.
Question 2

The average of 6 numbers is 48. If one number is removed, the average of the remaining numbers becomes 45. What is the number removed?

  1. A63
  2. B66
  3. C68
  4. D62
Show answer
Answer: (A) 63 Removed number = 6 × 48 − 5 × 45 = 63.
Question 3

The average of 6 numbers is 36. If one number is removed, the average of the remaining numbers becomes 33. What is the number removed?

  1. A52
  2. B49
  3. C51
  4. D57
Show answer
Answer: (C) 51 Removed number = 6 × 36 − 5 × 33 = 51.
Question 4

The average of 8 numbers is 37. If one number is removed, the average of the remaining numbers becomes 39. What is the number removed?

  1. A31
  2. B23
  3. C25
  4. D15
Show answer
Answer: (B) 23 Removed number = 8 × 37 − 7 × 39 = 23.
Question 5

The average of 10 numbers is 60. If one number is removed, the average of the remaining numbers becomes 58. What is the number removed?

  1. A73
  2. B80
  3. C78
  4. D88
Show answer
Answer: (C) 78 Removed number = 10 × 60 − 9 × 58 = 78.
Question 6

The average of 10 numbers is 43. If one number is removed, the average of the remaining numbers becomes 46. What is the number removed?

  1. A17
  2. B16
  3. C13
  4. D6
Show answer
Answer: (B) 16 Removed number = 10 × 43 − 9 × 46 = 16.
Question 7

The average of 5 numbers is 26. If one number is removed, the average of the remaining numbers becomes 23. What is the number removed?

  1. A37
  2. B39
  3. C38
  4. D43
Show answer
Answer: (C) 38 Removed number = 5 × 26 − 4 × 23 = 38.
Question 8

The average of 6 numbers is 37. If one number is removed, the average of the remaining numbers becomes 40. What is the number removed?

  1. A19
  2. B22
  3. C27
  4. D25
Show answer
Answer: (B) 22 Removed number = 6 × 37 − 5 × 40 = 22.
Question 9

The average of 8 numbers is 41. If one number is removed, the average of the remaining numbers becomes 44. What is the number removed?

  1. A20
  2. B15
  3. C12
  4. D28
Show answer
Answer: (A) 20 Removed number = 8 × 41 − 7 × 44 = 20.
Question 10

The average of 10 numbers is 57. If one number is removed, the average of the remaining numbers becomes 60. What is the number removed?

  1. A31
  2. B30
  3. C33
  4. D29
Show answer
Answer: (B) 30 Removed number = 10 × 57 − 9 × 60 = 30.
Question 11

The average of 5 numbers is 51. If one number is removed, the average of the remaining numbers becomes 49. What is the number removed?

  1. A54
  2. B59
  3. C62
  4. D61
Show answer
Answer: (B) 59 Removed number = 5 × 51 − 4 × 49 = 59.
Question 12

The average of 5 numbers is 48. If one number is removed, the average of the remaining numbers becomes 52. What is the number removed?

  1. A27
  2. B37
  3. C32
  4. D31
Show answer
Answer: (C) 32 Removed number = 5 × 48 − 4 × 52 = 32.
Question 13

The average of 5 numbers is 27. If one number is removed, the average of the remaining numbers becomes 29. What is the number removed?

  1. A17
  2. B20
  3. C24
  4. D19
Show answer
Answer: (D) 19 Removed number = 5 × 27 − 4 × 29 = 19.
Question 14

The average of 5 numbers is 52. If one number is removed, the average of the remaining numbers becomes 56. What is the number removed?

  1. A39
  2. B36
  3. C31
  4. D41
Show answer
Answer: (B) 36 Removed number = 5 × 52 − 4 × 56 = 36.
Question 15

The average of 5 numbers is 24. If one number is removed, the average of the remaining numbers becomes 28. What is the number removed?

  1. A13
  2. B8
  3. C9
  4. D3
Show answer
Answer: (B) 8 Removed number = 5 × 24 − 4 × 28 = 8.
Question 16

The average of 5 numbers is 23. If one number is removed, the average of the remaining numbers becomes 25. What is the number removed?

  1. A20
  2. B17
  3. C15
  4. D16
Show answer
Answer: (C) 15 Removed number = 5 × 23 − 4 × 25 = 15.
Question 17

The average of 6 numbers is 23. If one number is removed, the average of the remaining numbers becomes 26. What is the number removed?

  1. A7
  2. B10
  3. C8
  4. D9
Show answer
Answer: (C) 8 Removed number = 6 × 23 − 5 × 26 = 8.
Question 18

The average of 10 numbers is 24. If one number is removed, the average of the remaining numbers becomes 22. What is the number removed?

  1. A43
  2. B32
  3. C42
  4. D40
Show answer
Answer: (C) 42 Removed number = 10 × 24 − 9 × 22 = 42.

These are RankerClub practice questions written in the CDS pattern. They are not official SSC/IBPS/RRB papers.

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