Вроде это
program Lab1_2;
const n= 5; m=5;
var a:array[1..n,1..m] of real;
s,i,j:integer;
begin
randomize;
for i:=1 to n do
begin
for j:=1 to m do
begin
a[i,j]:=random(10);
write(a[i,j]:4);
end;
writeln;
end;
s:=0;
for i:=1 to n do begin
for j:=1 to m do begin
if (a[i,j] mod 2) = 0 then begin
s:=s+a[i,j];
end;
end;
end;
writeln('summa: ',s);
readln;
end.
(если ошибся сори!)