JEE Math Practice Question
The mean and standard deviation of 20 observations are found to be 10 and 2 , respectively. On rechecking, it was found that an observation by mistake was taken 8 instead of 12. The correct standard deviation is
- A.1.94
- B.$$\sqrt{3.96}$$
- C.$$\sqrt{3.86}$$
- D.1.8
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