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The average of 10 numbers is 30. If at the time of calculation one number was wrongly taken as 36 instead of 69, then what will be the correct average?

  1. A
    33
  2. B
    33.3
  3. C
    36
  4. D
    39

Solution & Step-by-step Explanation

Given:
Number of observations (n) =10

Incorrect Average =30

Incorrect Sum =30×10=300

Now, find the correction:

Wrong value taken =36

Correct value to be taken =69

Difference (Correction) =69−36=+33

Correct Sum =300+33=333

Correct Average =
n
Correct Sum

=
10
333

=33.3

Practice this question

Try it yourself before checking the explanation above.

The average of 10 numbers is 30. If at the time of calculation one number was wrongly taken as 36 instead of 69, then what will be the correct average?
A
33
B
33.3
C
36
D
39

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