Is this an LL(1) grammar? How to solve First - Follow conflict?
Your factoring is wrong. It should be (written as regular espressions):

$\begin{align*}
  R
    &amp;\to (L \mid \operatorname{num}) (+ R)^*
\end{align*}$ 

Thus the grammar with left recursion fixed is:

$\begin{align*}
   S  &amp;\to L = R \\
   L  &amp;\to * L \mid \operatorname{id} \\
   R  &amp;\to L R' \mid \operatorname{num} R' \\
   R' &amp;\to + R R' \mid \varepsilon
\end{align*}$

You can check that this doesn't have conflicts.