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The mean and variance of 20 observations...

The mean and variance of 20 observations are found to be 10 and 4 respectively. On rechecking, it was found that an observation 8 is incorrect. If the wrong observation is omitted, then the correct variance is

A

`4.01`

B

`3.99`

C

`3.98`

D

`4.02`

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The correct Answer is:
B
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