[tex]\it n:6=a\ \ rest\ 4 \Rightarrow n=6a+4|_{+2} \Rightarrow n+2=6a+6 \Rightarrow n+2\in M_6\\ \\ n:8=b\ \ rest\ 6 \Rightarrow n=8b+6|_{+2} \Rightarrow n+2=8b+8 \Rightarrow n+2\in M_8\\ \\ n:9=c\ \ rest\ 7 \Rightarrow n=9c+7|_{+2} \Rightarrow n+2=9c+9 \Rightarrow n+2\in M_9[/tex]
[tex]\it n+2=\Big[6,\ 8,\ 9\Big] \Rightarrow n+2=72 \Rightarrow n=70[/tex]
