engineering recuitment AAI ATC Junior Executive 2025 Mock Test Series Mathematics Statistics Variance and Standard Deviation
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
1
\(\frac{4}{5}\)
2
\(\frac{77}{12}\)
3
\(\frac{5}{4}\)
4
\(\frac{105}{4}\)