9709 P51 - Nov 2021 - Q2
2539
A summary of 40 values of \(x\) gives the following information:
\(\Sigma(x-k) = 520\), \(\Sigma(x-k)^2 = 9640\),
where \(k\) is a constant.
(a) Given that the mean of these 40 values of \(x\) is 34, find the value of \(k\).
(b) Find the variance of these 40 values of \(x\).
