Without Operand Forwarding:
$\begin{array} {|r|r|}\hline 1 & 2 & 3 & 4 & 5&6&7&8&9&10&11&12&13&14 \\\hline IF & ID & EX & WB \\ \hline & IF& -- & -- & ID & EX & EX & EX & WB & & & & & \\ \hline & & -- & --& IF& --& -- &-- & --& ID & EX & EX& EX& WB \\ \hline \end{array}$
With Operand forwarding:
Assuming Operand forwarding is from EX to EX stage
$\begin{array} {|r|r|}\hline 1 & 2 & 3 & 4 & 5&6&7&8&9&10\\\hline IF & ID & EX & WB \\ \hline & IF& ID &EX & EX & EX & WB& \\ \hline & & IF & ID& --& --& EX &EX& EX& WB \\ \hline \end{array}$
So cycles saved = 14-10 = 4