Edexcel S2 2013 June — Question 2

Exam BoardEdexcel
ModuleS2 (Statistics 2)
Year2013
SessionJune
TopicCumulative distribution functions
TypeContinuous CDF with polynomial pieces

2. The continuous random variable \(Y\) has cumulative distribution function $$\mathrm { F } ( y ) = \left\{ \begin{array} { c c } 0 & y < 0
\frac { 1 } { 4 } \left( y ^ { 3 } - 4 y ^ { 2 } + k y \right) & 0 \leqslant y \leqslant 2
1 & y > 2 \end{array} \right.$$ where \(k\) is a constant.
  1. Find the value of \(k\).
  2. Find the probability density function of \(Y\), specifying it for all values of \(y\).
  3. Find \(\mathrm { P } ( Y > 1 )\).