CAIE S2 2019 March — Question 7

Exam BoardCAIE
ModuleS2 (Statistics 2)
Year2019
SessionMarch
TopicContinuous Probability Distributions and Random Variables
TypePiecewise PDF with multiple regions

7
\includegraphics[max width=\textwidth, alt={}, center]{a93e5413-6ad8-4957-8efd-470cf79792e2-12_428_693_260_724} A random variable \(X\) has probability density function given by $$f ( x ) = \begin{cases} ( \sqrt { } 2 ) \cos x & 0 \leqslant x \leqslant \frac { 1 } { 4 } \pi
0 & \text { otherwise } \end{cases}$$ as shown in the diagram.
  1. Find \(\mathrm { P } \left( X > \frac { 1 } { 6 } \pi \right)\).
  2. Find the median of \(X\).
  3. Find \(\mathrm { E } ( X )\).
    If you use the following lined page to complete the answer(s) to any question(s), the question number(s) must be clearly shown.