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The mean of 5 observation is 25, if one of the observation is excluded the mean becomes 20. The excluded number is


A) 45

B) 40

C) 20

D) 10

Correct Answer:
A) 45

Description for Correct answer:

The mean of observation = 25

The sum of 5 numbers = 5 X25 = 125

The mean of 4 observation = 20

The sum of 4 numbers=4X20 = 80

The excluded number = 125-80=45


Part of solved TNPSC Question Paper-2014 questions and answers : Exams >> TNPSC >> TNPSC Question Paper-2014




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