Calculate the MAD. Answer to one decimal place

\begin{tabular}{|c|c|c|l|l|} \hline Step & Duration(Weeks) & Predecessors & Can Crash by & CrashCostperWeek \\ \hline A & 7 & - & 1 week & $750 \\ \hline B & 6 & - & 2 weeks & $750 \\ \hline C & 4 & A, B & 1 week & $1000 \\ \hline D & 3 & A & 2 weeks & $150 \\ \hline E & 6 & C & 3 weeks & $500 \\ \hline F & 1 & D.E & - & - \\ \hline \end{tabular}