This question has already been answered:
uses crt; var i,k:integer; a,b:byte; begin clrscr; k:=0; i:=999; while i<9999 do begin i:=i+1; a:=i div 100 mod 10; b:=i div 10 mod 10; if(i mod 45=0)and(((a=9)and(b=7))or((a=7)and(b=9))) then begin writeln(i); k:=k+1; end; end; write('Всего чисел=',k); readln end.