506mn78¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

divided by 8 with remainder 2

⇒n78¯¯¯¯¯¯¯¯

divided by 8 with remainder 2

=> n = 1 ; 3 ; 5 ; 7 ; 9

506mn78¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯⋮9⇒26+m+n⋮9

If n = 1,then27+m⋮9⇒m=0;9

If n = 3.then 29+m⋮9⇒m=7

If n = 5,then 31+m⋮9⇒m=5

If n = 7.then 33+m⋮9⇒m=3

If n = 9,then 35+m⋮9⇒m=1

Hence,(m ; n) = (0 ; 1) ; (9 ; 1) ; (7 ; 3) ; (5 ; 5) ; (3 ; 7) ; (1 ; 9)

\(\overline{506mn78}\)divided by 8 with remainder 2

\(\Rightarrow\overline{n78}\)divided by 8 with remainder 2

=> n = 1 ; 3 ; 5 ; 7 ; 9

\(\overline{506mn78}⋮9\Rightarrow26+m+n⋮9\)

If n = 1,then\(27+m⋮9\Rightarrow m=0;9\)

If n = 3.then \(29+m⋮9\Rightarrow m=7\)

If n = 5,then \(31+m⋮9\Rightarrow m=5\)

If n = 7.then \(33+m⋮9\Rightarrow m=3\)

If n = 9,then \(35+m⋮9\Rightarrow m=1\)

Hence,(m ; n) = (0 ; 1) ; (9 ; 1) ; (7 ; 3) ; (5 ; 5) ; (3 ; 7) ; (1 ; 9)