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The average age of a number of persons i...

The average age of a number of persons in a group’ was calculated as 35 years, which was 2.5 years more than the correct average as there was an error in recording the age of two persons as 38.5 years and 40 years instead of 29 years and 22 years respectively. The number of persons in the group was:
एक समूह में कुछ लोगों की औसत उम्र की गणना 35 वर्ष की गयी, जो वास्तविक औसत से 2.5 वर्ष अधिक थी, क्‍योंकि दो व्यक्तियों की उम्र 29 वर्ष तथा 22 वर्ष के स्थान पर भूलवश 38.5 वर्ष तथा 40 वर्ष दर्ज कर ली गयी थी | इस समूह में लोगों की संख्या कितनी थी ?

A

11

B

12

C

15

D

13

Text Solution

Verified by Experts

The correct Answer is:
D
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GAGAN PRATAP -AVERAGE-Multiple Choice Questions
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  2. The average of 100 numbers is 63, but it was found that 2 numbers 37 &...

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  3. The average age of a number of persons in a group’ was calculated as 3...

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  4. The average of the ages of a group of 65 men is 32 years. If 5 men...

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  5. The average of 18 numbers is 37.5. If six numbers of average x are add...

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  6. The average weight of some students in a class was 58.4kg. When 5 stud...

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  7. The average weight of the students in a group 75.4 kg. Later on, four ...

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  8. The average weight of a certain number of students in a group is 72 kg...

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  9. While tabulation of marks scored in an examination by the students of ...

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  10. The average of n observations is 40. If one observation of value 80 is...

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  11. The average age of 24 students is 15.5 years. The age of the teacher i...

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  12. Three numbers are such that if the average of any two of them is added...

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  13. The average of eleven numbers is 68. The average of the first four num...

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  14. The average of thirteen numbers is 80. The average of the first five n...

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  15. The average of 24 numbers is 56. The average of the first 10 numbers i...

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  16. The average marks of 30 boys is 88, and when the top scores were exclu...

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  17. A batsman scores 92 runs in his 15th innings, which increases his batt...

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  18. A batsman makes 100 runs in the 25th match of his career. His average ...

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  19. The average run of a batsman in his 23 matches is 62. He scores 122 in...

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  20. A cricket batsman had certain average of runs in his 91 innings. In th...

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