JEE Math Practice Question
The mean and variance of the marks obtained by the students in a test are 10 and 4 respectively. Later, the marks of one of the students is increased from 8 to 12. If the new mean of the marks is 10.2, then their new variance is equal to :
- A.3.92
- B.4.08
- C.3.96
- D.4.04
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