JAMB - Mathematics (2013 - No. 26)
If the variance of 3+x, 6, 4, x and 7-x is 4 and the mean is 5, find the standard deviation
\(\sqrt{3}\)
2
3
\(\sqrt{2}\)
Vysvetlenie
Let \(\delta^2\) and \(\delta\) denote the variance and standard deviation of the distribution respectively.
But \(\delta^2\) = 4 (given)
Hence \(\delta\) = \(\sqrt{4}\) = 2
But \(\delta^2\) = 4 (given)
Hence \(\delta\) = \(\sqrt{4}\) = 2