Answer :
[tex]\left\begin{array}{ccc}24=3\cdot8\\12=3\cdot4\end{array}\right\}24\cdot12=3\cdot8\cdot3\cdot4\\\\\\\left\begin{array}{ccc}24=144:6\\12=36:3\end{array}\right\}24\cdot12=144:6\cdot36:6\\\\\\\left\begin{array}{ccc}24=96:4\\12=48:4\end{array}\right\}24\cdot12=96:4\cdot48:4\\\\\\\left\begin{array}{ccc}24=16+8\\12=9+3\end{array}\right\}24\cdot12=(16+8)\cdot(9+3)\\sequence\ of\ key:16+18=M+;\ 9+3=\times MR=\\\\\\[/tex]
