7 The time, \(T\) hours, that the supporters of Bracken Football Club have to queue in order to obtain their Cup Final tickets has the following probability density function.
$$\mathrm { f } ( t ) = \begin{cases} \frac { 1 } { 5 } & 0 \leqslant t < 3
\frac { 1 } { 45 } t ( 6 - t ) & 3 \leqslant t \leqslant 6
0 & \text { otherwise } \end{cases}$$
- Sketch the graph of f.
- Write down the value of \(\mathrm { P } ( T = 3 )\).
- Find the probability that a randomly selected supporter has to queue for at least 3 hours in order to obtain tickets.
- Show that the median queuing time is 2.5 hours.
- Calculate P (median \(< T <\) mean).