According to the meaning of the question (10m+l) (10l+m) =1000m+10l+10J+x,

100ml+ 10(m^2+l^2)+ml= 100( 10m+l)+ 10j+x,①

To approach ml to 10m+l, l=9, ① becomes.

900m+ 10(m^2+8 1)+9m= 100( 10m+9)+ 10j+x，

900m+ 10m^2+8 10+9m= 1000m+900+ 10j+x，

Finishing to10m2-91m-90-10j-x = 0,

M( 10m-9 1) is negative, and the above equation has no solution.

There is no solution to this problem in decimal system.