JEE Math Practice Question
If the mean and variance of five observations are $$\frac{24}{5}$$ and $$\frac{194}{25}$$ respectively and the mean of the first four observations is $$\frac{7}{2}$$, then the variance of the first four observations in equal to
- A.$$\frac{5}{4}$$
- B.$$\frac{4}{5}$$
- C.$$\frac{105}{4}$$
- D.$$\frac{77}{12}$$
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