9709 P63 - Nov 2013 - Q5
3244
(a) The random variable X is normally distributed with mean 82 and standard deviation 7.4. Find the value of q such that \(P(82-q < X < 82+q) = 0.44\).
(b) The random variable Y is normally distributed with mean \(\mu\) and standard deviation \(\sigma\). It is given that \(5\mu = 2\sigma^2\) and that \(P(Y < \frac{1}{2}\mu) = 0.281\). Find the values of \(\mu\) and \(\sigma\).
