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The mean of five numbers is 30. If one number is excluded, their mean becomes 28. The excluded number is

Options

  1. A28
  2. B30
  3. C35
  4. D38

Correct answer

D. 38

Step-by-step solution

Mean of 5 numbers = 30 Total sum of 5 numbers =30 5=150 After excluded one number Mean of 4 numbers will be =28 Total sum of 4 numbers =4 28=112 Thus, excluded number =( sum of 5 numbers - sum of 4 numbers )=150-112=38 Option (D) is correct.

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