CAIE S1 2007 November — Question 4

Exam BoardCAIE
ModuleS1 (Statistics 1)
Year2007
SessionNovember
TopicNormal Distribution
TypeMultiple probability calculations

4
\includegraphics[max width=\textwidth, alt={}, center]{1a10471c-5810-44ca-9353-c2c76e190a2b-2_542_876_1425_632} The random variable \(X\) has a normal distribution with mean 4.5. It is given that \(\mathrm { P } ( X > 5.5 ) = 0.0465\) (see diagram).
  1. Find the standard deviation of \(X\).
  2. Find the probability that a random observation of \(X\) lies between 3.8 and 4.8.