After Plowing Through Contracts for a Decade, the Contract Writer

Short Answer

After plowing through contracts for a decade, the contract writer knew about how long it took to crank out the material necessary to satisfy a contract's requirements. The distribution could be modeled using the data provided in this table.
$$\begin{array} { | c | c | } \hline \begin{array} { c } \text { Number of } \\\text { Weeks }\end{array} & \begin{array} { c } \text { Random } \\\text { Number Range }\end{array} \\\hline 2 & 0 - 5 \\\hline 3 & 6 - 15 \\\hline 4 & 16 - 35 \\\hline 5 & 36 - 80 \\\hline 6 & 81 - 99 \\\hline\end{array}$$
-If the ten numbers generated are 87, 84, 99, 18, 81, 75, 32, 87, 46, and 35, what is the resultant expected average completion time?