Averages Competitive Exams
100 questions · Mathematics
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Question 1 of 100
The average of 5 consecutive integers starting from 27 is:
ExplanationFor an odd number of consecutive integers, the average is always the middle number. The middle of 5 numbers starting from 27 is 29.
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Question 2 of 100
The average of 4 numbers is 30. If 3 of these numbers are 24, 79, 70, what is the missing number?
ExplanationTotal sum of 4 numbers = 30 × 4 = 120. Sum of given = 173. Missing = 120 - 173 = -53. Tip: Sum = Average × N is the most useful formula here.
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Question 3 of 100
The average of 6 numbers is 60. If 5 of these numbers are 43, 14, 10, 23, 79, what is the missing number?
ExplanationTotal sum of 6 numbers = 60 × 6 = 360. Sum of given = 169. Missing = 360 - 169 = 191. Tip: Sum = Average × N is the most useful formula here.
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Question 4 of 100
Find the average of 50, 98, 80, 68, and 57.
ExplanationAverage = Sum / Count. Sum = 353. Count = 5. Avg = 70.6. Tip: Ensure all numbers are in the same unit before averaging.
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Question 5 of 100
The average of 9 consecutive integers starting from 37 is:
ExplanationFor an odd number of consecutive integers, the average is always the middle number. The middle of 9 numbers starting from 37 is 41.
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Question 6 of 100
The average of 6 numbers is 33. If 5 of these numbers are 43, 30, 62, 35, 62, what is the missing number?
ExplanationTotal sum of 6 numbers = 33 × 6 = 198. Sum of given = 232. Missing = 198 - 232 = -34. Tip: Sum = Average × N is the most useful formula here.
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Question 7 of 100
The average of 7 consecutive integers starting from 4 is:
ExplanationFor an odd number of consecutive integers, the average is always the middle number. The middle of 7 numbers starting from 4 is 7.
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Question 8 of 100
The average age of 30 students in a class is 17 years. When the teacher's age is included, the average becomes 18 years. What is the age of the teacher?
ExplanationSum of students' ages = 30 × 17 = 510. Sum with teacher = 31 × 18 = 558. Teacher's age = 558 - 510 = 48. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 9 of 100
Section A has 24 students with an average score of 51. Section B has 12 students with an average score of 57. Find the combined average score.
ExplanationTotal score A = 24×51 = 1224. Total B = 12×57 = 684. Combined avg = (1224 + 684) / 36 = 53.0. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 10 of 100
The average of 6 numbers is 45. If 5 of these numbers are 13, 21, 35, 46, 60, what is the missing number?
ExplanationTotal sum of 6 numbers = 45 × 6 = 270. Sum of given = 175. Missing = 270 - 175 = 95. Tip: Sum = Average × N is the most useful formula here.
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Question 11 of 100
The average age of 20 students in a class is 20 years. When the teacher's age is included, the average becomes 22 years. What is the age of the teacher?
ExplanationSum of students' ages = 20 × 20 = 400. Sum with teacher = 21 × 22 = 462. Teacher's age = 462 - 400 = 62. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 12 of 100
The average of 5 consecutive integers starting from 42 is:
ExplanationFor an odd number of consecutive integers, the average is always the middle number. The middle of 5 numbers starting from 42 is 44.
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Question 13 of 100
Section A has 10 students with an average score of 42. Section B has 10 students with an average score of 47. Find the combined average score.
ExplanationTotal score A = 10×42 = 420. Total B = 10×47 = 470. Combined avg = (420 + 470) / 20 = 44.5. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 14 of 100
Section A has 12 students with an average score of 47. Section B has 10 students with an average score of 67. Find the combined average score.
ExplanationTotal score A = 12×47 = 564. Total B = 10×67 = 670. Combined avg = (564 + 670) / 22 = 56.09. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 15 of 100
The average of 7 consecutive integers starting from 49 is:
ExplanationFor an odd number of consecutive integers, the average is always the middle number. The middle of 7 numbers starting from 49 is 52.
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Question 16 of 100
Find the average of 58, 38, 18, 56, and 50.
ExplanationAverage = Sum / Count. Sum = 220. Count = 5. Avg = 44.0. Tip: Ensure all numbers are in the same unit before averaging.
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Question 17 of 100
The average age of 26 students in a class is 15 years. When the teacher's age is included, the average becomes 16 years. What is the age of the teacher?
ExplanationSum of students' ages = 26 × 15 = 390. Sum with teacher = 27 × 16 = 432. Teacher's age = 432 - 390 = 42. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 18 of 100
The average of 9 consecutive integers starting from 31 is:
ExplanationFor an odd number of consecutive integers, the average is always the middle number. The middle of 9 numbers starting from 31 is 35.
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Question 19 of 100
The average age of 40 students in a class is 13 years. When the teacher's age is included, the average becomes 14 years. What is the age of the teacher?
ExplanationSum of students' ages = 40 × 13 = 520. Sum with teacher = 41 × 14 = 574. Teacher's age = 574 - 520 = 54. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 20 of 100
The average age of 34 students in a class is 15 years. When the teacher's age is included, the average becomes 17 years. What is the age of the teacher?
ExplanationSum of students' ages = 34 × 15 = 510. Sum with teacher = 35 × 17 = 595. Teacher's age = 595 - 510 = 85. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 21 of 100
The average of 4 numbers is 23. If 3 of these numbers are 23, 16, 37, what is the missing number?
ExplanationTotal sum of 4 numbers = 23 × 4 = 92. Sum of given = 76. Missing = 92 - 76 = 16. Tip: Sum = Average × N is the most useful formula here.
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Question 22 of 100
The average of 9 consecutive integers starting from 44 is:
ExplanationFor an odd number of consecutive integers, the average is always the middle number. The middle of 9 numbers starting from 44 is 48.
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Question 23 of 100
Find the average of 17, 76, 39, 28, and 77.
ExplanationAverage = Sum / Count. Sum = 237. Count = 5. Avg = 47.4. Tip: Ensure all numbers are in the same unit before averaging.
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Question 24 of 100
Find the average of 36, 63, 87, 11, and 52.
ExplanationAverage = Sum / Count. Sum = 249. Count = 5. Avg = 49.8. Tip: Ensure all numbers are in the same unit before averaging.
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Question 25 of 100
Section A has 25 students with an average score of 60. Section B has 26 students with an average score of 41. Find the combined average score.
ExplanationTotal score A = 25×60 = 1500. Total B = 26×41 = 1066. Combined avg = (1500 + 1066) / 51 = 50.31. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 26 of 100
The average of 5 consecutive integers starting from 49 is:
ExplanationFor an odd number of consecutive integers, the average is always the middle number. The middle of 5 numbers starting from 49 is 51.
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Question 27 of 100
Section A has 12 students with an average score of 71. Section B has 13 students with an average score of 69. Find the combined average score.
ExplanationTotal score A = 12×71 = 852. Total B = 13×69 = 897. Combined avg = (852 + 897) / 25 = 69.96. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 28 of 100
The average of 3 consecutive integers starting from 27 is:
ExplanationFor an odd number of consecutive integers, the average is always the middle number. The middle of 3 numbers starting from 27 is 28.
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Question 29 of 100
The average of 4 numbers is 37. If 3 of these numbers are 37, 20, 39, what is the missing number?
ExplanationTotal sum of 4 numbers = 37 × 4 = 148. Sum of given = 96. Missing = 148 - 96 = 52. Tip: Sum = Average × N is the most useful formula here.
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Question 30 of 100
The average of 4 numbers is 50. If 3 of these numbers are 62, 77, 69, what is the missing number?
ExplanationTotal sum of 4 numbers = 50 × 4 = 200. Sum of given = 208. Missing = 200 - 208 = -8. Tip: Sum = Average × N is the most useful formula here.
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Question 31 of 100
The average of 5 numbers is 24. If 4 of these numbers are 75, 58, 32, 78, what is the missing number?
ExplanationTotal sum of 5 numbers = 24 × 5 = 120. Sum of given = 243. Missing = 120 - 243 = -123. Tip: Sum = Average × N is the most useful formula here.
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Question 32 of 100
The average age of 31 students in a class is 13 years. When the teacher's age is included, the average becomes 15 years. What is the age of the teacher?
ExplanationSum of students' ages = 31 × 13 = 403. Sum with teacher = 32 × 15 = 480. Teacher's age = 480 - 403 = 77. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 33 of 100
Section A has 27 students with an average score of 56. Section B has 13 students with an average score of 55. Find the combined average score.
ExplanationTotal score A = 27×56 = 1512. Total B = 13×55 = 715. Combined avg = (1512 + 715) / 40 = 55.67. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 34 of 100
The average age of 32 students in a class is 18 years. When the teacher's age is included, the average becomes 19 years. What is the age of the teacher?
ExplanationSum of students' ages = 32 × 18 = 576. Sum with teacher = 33 × 19 = 627. Teacher's age = 627 - 576 = 51. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 35 of 100
The average age of 29 students in a class is 13 years. When the teacher's age is included, the average becomes 14 years. What is the age of the teacher?
ExplanationSum of students' ages = 29 × 13 = 377. Sum with teacher = 30 × 14 = 420. Teacher's age = 420 - 377 = 43. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 36 of 100
Find the average of 86, 70, 73, 70, and 14.
ExplanationAverage = Sum / Count. Sum = 313. Count = 5. Avg = 62.6. Tip: Ensure all numbers are in the same unit before averaging.
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Question 37 of 100
Section A has 29 students with an average score of 50. Section B has 16 students with an average score of 66. Find the combined average score.
ExplanationTotal score A = 29×50 = 1450. Total B = 16×66 = 1056. Combined avg = (1450 + 1056) / 45 = 55.69. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 38 of 100
The average age of 32 students in a class is 16 years. When the teacher's age is included, the average becomes 18 years. What is the age of the teacher?
ExplanationSum of students' ages = 32 × 16 = 512. Sum with teacher = 33 × 18 = 594. Teacher's age = 594 - 512 = 82. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 39 of 100
Section A has 26 students with an average score of 55. Section B has 28 students with an average score of 70. Find the combined average score.
ExplanationTotal score A = 26×55 = 1430. Total B = 28×70 = 1960. Combined avg = (1430 + 1960) / 54 = 62.78. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 40 of 100
The average age of 35 students in a class is 12 years. When the teacher's age is included, the average becomes 14 years. What is the age of the teacher?
ExplanationSum of students' ages = 35 × 12 = 420. Sum with teacher = 36 × 14 = 504. Teacher's age = 504 - 420 = 84. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 41 of 100
The average of 5 consecutive integers starting from 5 is:
ExplanationFor an odd number of consecutive integers, the average is always the middle number. The middle of 5 numbers starting from 5 is 7.
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Question 42 of 100
The average age of 29 students in a class is 16 years. When the teacher's age is included, the average becomes 18 years. What is the age of the teacher?
ExplanationSum of students' ages = 29 × 16 = 464. Sum with teacher = 30 × 18 = 540. Teacher's age = 540 - 464 = 76. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 43 of 100
Find the average of 82, 83, 71, 86, and 57.
ExplanationAverage = Sum / Count. Sum = 379. Count = 5. Avg = 75.8. Tip: Ensure all numbers are in the same unit before averaging.
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Question 44 of 100
The average of 6 numbers is 20. If 5 of these numbers are 48, 74, 70, 30, 51, what is the missing number?
ExplanationTotal sum of 6 numbers = 20 × 6 = 120. Sum of given = 273. Missing = 120 - 273 = -153. Tip: Sum = Average × N is the most useful formula here.
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Question 45 of 100
Section A has 16 students with an average score of 43. Section B has 15 students with an average score of 44. Find the combined average score.
ExplanationTotal score A = 16×43 = 688. Total B = 15×44 = 660. Combined avg = (688 + 660) / 31 = 43.48. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 46 of 100
Section A has 18 students with an average score of 57. Section B has 29 students with an average score of 53. Find the combined average score.
ExplanationTotal score A = 18×57 = 1026. Total B = 29×53 = 1537. Combined avg = (1026 + 1537) / 47 = 54.53. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 47 of 100
The average of 5 numbers is 37. If 4 of these numbers are 42, 78, 73, 34, what is the missing number?
ExplanationTotal sum of 5 numbers = 37 × 5 = 185. Sum of given = 227. Missing = 185 - 227 = -42. Tip: Sum = Average × N is the most useful formula here.
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Question 48 of 100
Section A has 12 students with an average score of 62. Section B has 12 students with an average score of 56. Find the combined average score.
ExplanationTotal score A = 12×62 = 744. Total B = 12×56 = 672. Combined avg = (744 + 672) / 24 = 59.0. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 49 of 100
The average of 7 numbers is 55. If 6 of these numbers are 22, 36, 45, 59, 46, 23, what is the missing number?
ExplanationTotal sum of 7 numbers = 55 × 7 = 385. Sum of given = 231. Missing = 385 - 231 = 154. Tip: Sum = Average × N is the most useful formula here.
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Question 50 of 100
The average of 5 numbers is 58. If 4 of these numbers are 25, 24, 65, 25, what is the missing number?
ExplanationTotal sum of 5 numbers = 58 × 5 = 290. Sum of given = 139. Missing = 290 - 139 = 151. Tip: Sum = Average × N is the most useful formula here.
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Question 51 of 100
The average age of 33 students in a class is 14 years. When the teacher's age is included, the average becomes 16 years. What is the age of the teacher?
ExplanationSum of students' ages = 33 × 14 = 462. Sum with teacher = 34 × 16 = 544. Teacher's age = 544 - 462 = 82. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 52 of 100
The average age of 22 students in a class is 20 years. When the teacher's age is included, the average becomes 21 years. What is the age of the teacher?
ExplanationSum of students' ages = 22 × 20 = 440. Sum with teacher = 23 × 21 = 483. Teacher's age = 483 - 440 = 43. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 53 of 100
The average age of 39 students in a class is 18 years. When the teacher's age is included, the average becomes 19 years. What is the age of the teacher?
ExplanationSum of students' ages = 39 × 18 = 702. Sum with teacher = 40 × 19 = 760. Teacher's age = 760 - 702 = 58. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 54 of 100
The average age of 38 students in a class is 16 years. When the teacher's age is included, the average becomes 17 years. What is the age of the teacher?
ExplanationSum of students' ages = 38 × 16 = 608. Sum with teacher = 39 × 17 = 663. Teacher's age = 663 - 608 = 55. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 55 of 100
The average age of 27 students in a class is 19 years. When the teacher's age is included, the average becomes 21 years. What is the age of the teacher?
ExplanationSum of students' ages = 27 × 19 = 513. Sum with teacher = 28 × 21 = 588. Teacher's age = 588 - 513 = 75. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 56 of 100
Find the average of 64, 19, 11, 43, and 47.
ExplanationAverage = Sum / Count. Sum = 184. Count = 5. Avg = 36.8. Tip: Ensure all numbers are in the same unit before averaging.
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Question 57 of 100
The average age of 36 students in a class is 13 years. When the teacher's age is included, the average becomes 14 years. What is the age of the teacher?
ExplanationSum of students' ages = 36 × 13 = 468. Sum with teacher = 37 × 14 = 518. Teacher's age = 518 - 468 = 50. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 58 of 100
The average of 9 consecutive integers starting from 15 is:
ExplanationFor an odd number of consecutive integers, the average is always the middle number. The middle of 9 numbers starting from 15 is 19.
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Question 59 of 100
The average of 4 numbers is 22. If 3 of these numbers are 67, 20, 21, what is the missing number?
ExplanationTotal sum of 4 numbers = 22 × 4 = 88. Sum of given = 108. Missing = 88 - 108 = -20. Tip: Sum = Average × N is the most useful formula here.
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Question 60 of 100
The average of 6 numbers is 34. If 5 of these numbers are 52, 74, 27, 41, 51, what is the missing number?
ExplanationTotal sum of 6 numbers = 34 × 6 = 204. Sum of given = 245. Missing = 204 - 245 = -41. Tip: Sum = Average × N is the most useful formula here.
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Question 61 of 100
Section A has 20 students with an average score of 49. Section B has 23 students with an average score of 79. Find the combined average score.
ExplanationTotal score A = 20×49 = 980. Total B = 23×79 = 1817. Combined avg = (980 + 1817) / 43 = 65.05. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 62 of 100
Find the average of 75, 27, 86, 63, and 60.
ExplanationAverage = Sum / Count. Sum = 311. Count = 5. Avg = 62.2. Tip: Ensure all numbers are in the same unit before averaging.
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Question 63 of 100
The average age of 37 students in a class is 16 years. When the teacher's age is included, the average becomes 17 years. What is the age of the teacher?
ExplanationSum of students' ages = 37 × 16 = 592. Sum with teacher = 38 × 17 = 646. Teacher's age = 646 - 592 = 54. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 64 of 100
The average age of 38 students in a class is 14 years. When the teacher's age is included, the average becomes 16 years. What is the age of the teacher?
ExplanationSum of students' ages = 38 × 14 = 532. Sum with teacher = 39 × 16 = 624. Teacher's age = 624 - 532 = 92. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 65 of 100
The average age of 23 students in a class is 12 years. When the teacher's age is included, the average becomes 13 years. What is the age of the teacher?
ExplanationSum of students' ages = 23 × 12 = 276. Sum with teacher = 24 × 13 = 312. Teacher's age = 312 - 276 = 36. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 66 of 100
The average age of 23 students in a class is 18 years. When the teacher's age is included, the average becomes 19 years. What is the age of the teacher?
ExplanationSum of students' ages = 23 × 18 = 414. Sum with teacher = 24 × 19 = 456. Teacher's age = 456 - 414 = 42. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 67 of 100
Find the average of 97, 83, 85, 32, and 49.
ExplanationAverage = Sum / Count. Sum = 346. Count = 5. Avg = 69.2. Tip: Ensure all numbers are in the same unit before averaging.
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Question 68 of 100
The average age of 38 students in a class is 18 years. When the teacher's age is included, the average becomes 19 years. What is the age of the teacher?
ExplanationSum of students' ages = 38 × 18 = 684. Sum with teacher = 39 × 19 = 741. Teacher's age = 741 - 684 = 57. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 69 of 100
Section A has 26 students with an average score of 48. Section B has 28 students with an average score of 71. Find the combined average score.
ExplanationTotal score A = 26×48 = 1248. Total B = 28×71 = 1988. Combined avg = (1248 + 1988) / 54 = 59.93. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 70 of 100
The average of 7 numbers is 31. If 6 of these numbers are 17, 72, 43, 28, 15, 71, what is the missing number?
ExplanationTotal sum of 7 numbers = 31 × 7 = 217. Sum of given = 246. Missing = 217 - 246 = -29. Tip: Sum = Average × N is the most useful formula here.
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Question 71 of 100
Section A has 27 students with an average score of 66. Section B has 25 students with an average score of 46. Find the combined average score.
ExplanationTotal score A = 27×66 = 1782. Total B = 25×46 = 1150. Combined avg = (1782 + 1150) / 52 = 56.38. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 72 of 100
The average of 7 consecutive integers starting from 36 is:
ExplanationFor an odd number of consecutive integers, the average is always the middle number. The middle of 7 numbers starting from 36 is 39.
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Question 73 of 100
The average of 7 consecutive integers starting from 13 is:
ExplanationFor an odd number of consecutive integers, the average is always the middle number. The middle of 7 numbers starting from 13 is 16.
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Question 74 of 100
The average of 6 numbers is 29. If 5 of these numbers are 21, 49, 51, 16, 75, what is the missing number?
ExplanationTotal sum of 6 numbers = 29 × 6 = 174. Sum of given = 212. Missing = 174 - 212 = -38. Tip: Sum = Average × N is the most useful formula here.
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Question 75 of 100
The average of 6 numbers is 41. If 5 of these numbers are 66, 30, 36, 52, 25, what is the missing number?
ExplanationTotal sum of 6 numbers = 41 × 6 = 246. Sum of given = 209. Missing = 246 - 209 = 37. Tip: Sum = Average × N is the most useful formula here.
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Question 76 of 100
Section A has 19 students with an average score of 59. Section B has 28 students with an average score of 45. Find the combined average score.
ExplanationTotal score A = 19×59 = 1121. Total B = 28×45 = 1260. Combined avg = (1121 + 1260) / 47 = 50.66. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 77 of 100
Section A has 27 students with an average score of 52. Section B has 15 students with an average score of 41. Find the combined average score.
ExplanationTotal score A = 27×52 = 1404. Total B = 15×41 = 615. Combined avg = (1404 + 615) / 42 = 48.07. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 78 of 100
Section A has 28 students with an average score of 52. Section B has 28 students with an average score of 61. Find the combined average score.
ExplanationTotal score A = 28×52 = 1456. Total B = 28×61 = 1708. Combined avg = (1456 + 1708) / 56 = 56.5. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 79 of 100
Section A has 29 students with an average score of 78. Section B has 10 students with an average score of 41. Find the combined average score.
ExplanationTotal score A = 29×78 = 2262. Total B = 10×41 = 410. Combined avg = (2262 + 410) / 39 = 68.51. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 80 of 100
The average age of 28 students in a class is 13 years. When the teacher's age is included, the average becomes 15 years. What is the age of the teacher?
ExplanationSum of students' ages = 28 × 13 = 364. Sum with teacher = 29 × 15 = 435. Teacher's age = 435 - 364 = 71. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 81 of 100
Section A has 10 students with an average score of 75. Section B has 30 students with an average score of 44. Find the combined average score.
ExplanationTotal score A = 10×75 = 750. Total B = 30×44 = 1320. Combined avg = (750 + 1320) / 40 = 51.75. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 82 of 100
Find the average of 84, 29, 50, 21, and 98.
ExplanationAverage = Sum / Count. Sum = 282. Count = 5. Avg = 56.4. Tip: Ensure all numbers are in the same unit before averaging.
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Question 83 of 100
Find the average of 69, 56, 28, 16, and 13.
ExplanationAverage = Sum / Count. Sum = 182. Count = 5. Avg = 36.4. Tip: Ensure all numbers are in the same unit before averaging.
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Question 84 of 100
The average of 7 numbers is 42. If 6 of these numbers are 43, 29, 26, 42, 76, 79, what is the missing number?
ExplanationTotal sum of 7 numbers = 42 × 7 = 294. Sum of given = 295. Missing = 294 - 295 = -1. Tip: Sum = Average × N is the most useful formula here.
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Question 85 of 100
Section A has 29 students with an average score of 59. Section B has 12 students with an average score of 44. Find the combined average score.
ExplanationTotal score A = 29×59 = 1711. Total B = 12×44 = 528. Combined avg = (1711 + 528) / 41 = 54.61. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 86 of 100
The average age of 30 students in a class is 16 years. When the teacher's age is included, the average becomes 17 years. What is the age of the teacher?
ExplanationSum of students' ages = 30 × 16 = 480. Sum with teacher = 31 × 17 = 527. Teacher's age = 527 - 480 = 47. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 87 of 100
Section A has 25 students with an average score of 65. Section B has 18 students with an average score of 41. Find the combined average score.
ExplanationTotal score A = 25×65 = 1625. Total B = 18×41 = 738. Combined avg = (1625 + 738) / 43 = 54.95. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 88 of 100
Find the average of 57, 65, 79, 70, and 96.
ExplanationAverage = Sum / Count. Sum = 367. Count = 5. Avg = 73.4. Tip: Ensure all numbers are in the same unit before averaging.
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Question 89 of 100
Find the average of 10, 75, 48, 36, and 13.
ExplanationAverage = Sum / Count. Sum = 182. Count = 5. Avg = 36.4. Tip: Ensure all numbers are in the same unit before averaging.
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Question 90 of 100
Section A has 28 students with an average score of 66. Section B has 24 students with an average score of 41. Find the combined average score.
ExplanationTotal score A = 28×66 = 1848. Total B = 24×41 = 984. Combined avg = (1848 + 984) / 52 = 54.46. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 91 of 100
Find the average of 21, 81, 76, 75, and 10.
ExplanationAverage = Sum / Count. Sum = 263. Count = 5. Avg = 52.6. Tip: Ensure all numbers are in the same unit before averaging.
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Question 92 of 100
The average age of 34 students in a class is 14 years. When the teacher's age is included, the average becomes 16 years. What is the age of the teacher?
ExplanationSum of students' ages = 34 × 14 = 476. Sum with teacher = 35 × 16 = 560. Teacher's age = 560 - 476 = 84. Tip: Shortcut: New Age = Old Avg + [Total new members × Increase in Avg].
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Question 93 of 100
Section A has 16 students with an average score of 69. Section B has 16 students with an average score of 58. Find the combined average score.
ExplanationTotal score A = 16×69 = 1104. Total B = 16×58 = 928. Combined avg = (1104 + 928) / 32 = 63.5. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 94 of 100
Section A has 20 students with an average score of 77. Section B has 20 students with an average score of 60. Find the combined average score.
ExplanationTotal score A = 20×77 = 1540. Total B = 20×60 = 1200. Combined avg = (1540 + 1200) / 40 = 68.5. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 95 of 100
The average of 6 numbers is 56. If 5 of these numbers are 45, 62, 80, 57, 56, what is the missing number?
ExplanationTotal sum of 6 numbers = 56 × 6 = 336. Sum of given = 300. Missing = 336 - 300 = 36. Tip: Sum = Average × N is the most useful formula here.
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Question 96 of 100
The average of 9 consecutive integers starting from 32 is:
ExplanationFor an odd number of consecutive integers, the average is always the middle number. The middle of 9 numbers starting from 32 is 36.
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Question 97 of 100
The average of 7 consecutive integers starting from 41 is:
ExplanationFor an odd number of consecutive integers, the average is always the middle number. The middle of 7 numbers starting from 41 is 44.
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Question 98 of 100
Section A has 18 students with an average score of 45. Section B has 25 students with an average score of 46. Find the combined average score.
ExplanationTotal score A = 18×45 = 810. Total B = 25×46 = 1150. Combined avg = (810 + 1150) / 43 = 45.58. Tip: Don't just average the two averages unless the number of students is exactly the same.
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Question 99 of 100
The average of 5 numbers is 27. If 4 of these numbers are 42, 32, 30, 71, what is the missing number?
ExplanationTotal sum of 5 numbers = 27 × 5 = 135. Sum of given = 175. Missing = 135 - 175 = -40. Tip: Sum = Average × N is the most useful formula here.
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Question 100 of 100
Find the average of 62, 96, 55, 32, and 53.
ExplanationAverage = Sum / Count. Sum = 298. Count = 5. Avg = 59.6. Tip: Ensure all numbers are in the same unit before averaging.
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