program ex ;
var v:array [1..20] of integer ;
     s,t,p,a,i,b,k :integer ;
     n:real;
     begin
write ('a=');
readln(a);
write ('b=');
readln (b);
write ('k=');
readln(k);
for i:=1 to p do begin
write ('v[',i,']=');
readln (v[i]);
end;
s:=0;
for i:=1 to p do
if ( v[i]>=a ) and (v[i]<=b) and (v[i] mod k =0) then begin
s:=s+v[i];
t:=t+1;
end;
if t=0 then
writeln ('media nu se poate calcula') else begin
n:=s/t;
writeln ('media este ',n:5:2);
end;
readln;
end.