1 The discrete random variable \(X\) has probability distribution defined by
$$\mathrm { P } ( X = r ) = k \left( r ^ { 2 } + 3 r \right) \text { for } r = 1,2,3,4,5 \text {, where } k \text { is a constant. }$$
- Complete the table below, using the copy in the Printed Answer Booklet giving the probabilities in terms of \(k\).
| \(r\) | 1 | 2 | 3 | 4 | 5 |
| \(\mathrm { P } ( X = r )\) | \(4 k\) | \(10 k\) | | | |
- Show that the value of \(k\) is 0.01 .
- Draw a graph to illustrate the distribution.
- Describe the shape of the distribution.
- Find each of the following.
- \(\mathrm { E } ( X )\)
- \(\operatorname { Var } ( X )\)