If the mean and variance of five observations are $\frac{24}{5}$ and $\frac{194}{25}$ respectively and the mean of first four observations is $\frac{7}{2}$, then the variance of the first four observations in equal to

  • [JEE MAIN 2024]
  • A

     $\frac{4}{5}$

  • B

     $\frac{77}{12}$

  • C

     $\frac{5}{4}$

  • D

     $\frac{105}{4}$

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  • [JEE MAIN 2014]