[giulichajari]

Código Delphi [-]
procedure TForm3.EcantidadChange(Sender: TObject);
begin
  Etotal.Text:=CurrToStr(StrToCurr(Ecantidad.Text)+ StrToCurr(ESUBTOTAL.Text));
end;

procedure TForm3.ECheque1Change(Sender: TObject);
begin
Edit2.Text:=CurrToStr(StrToCurr(Edit2.Text) + StrToCurr(ECheque1.Text));

end;

procedure TForm3.Echeque2Change(Sender: TObject);
begin
Edit2.Text:=CurrToStr(StrToCurr(Edit2.Text) + StrToCurr(ECheque2.Text));
end;

procedure TForm3.Echeque3Change(Sender: TObject);
begin
Edit2.Text:=CurrToStr(StrToCurr(Edit2.Text) + StrToCurr(ECheque3.Text));
end;

procedure TForm3.Echeque4Change(Sender: TObject);
begin
Edit2.Text:=CurrToStr(StrToCurr(Edit2.Text) + StrToCurr(ECheque4.Text));
end;

procedure TForm3.EcotizacionChange(Sender: TObject);
begin
  if (EcUSD.Text<>'') then
    begin
      ESUBTOTAL.Text:=CurrToStr(StrToCurr(EcUSD.Text) * StrToCurr(Ecotizacion.Text));
    end;

end;

procedure TForm3.EcUSDChange(Sender: TObject);
begin
if (Ecotizacion.Text<>'') then
   begin
      ESUBTOTAL.Text:=CurrToStr(StrToCurr(EcUSD.Text) * StrToCurr(Ecotizacion.Text));
   end;
end;

procedure TForm3.Edit2Change(Sender: TObject);
begin



  if (Edit2.Text<>'') then
     begin
      Edit5.Text:=CurrToStr(StrToCurr(Edeuda.Text) - StrToCurr(Edit2.Text));
     end;
end;

procedure TForm3.ESUBTOTALChange(Sender: TObject);
begin
if (Ecantidad.Text='') then
   begin
    Etotal.Text:=ESUBTOTAL.Text;
   end
   else
    begin

      Etotal.Text:=CurrToStr(StrToCurr(ESUBTOTAL.Text) + StrToCurr(Ecantidad.Text));
    end;

end;


procedure TForm3.EtotalChange(Sender: TObject);
begin
Edit2.Text:=CurrToStr(StrToCurr(Etotal.Text)+StrToCurr(ECheque1.Text)+StrToCurr(ECheque2.Text)+StrTo  Curr(ECheque3.Text)+ StrToCurr(ECheque4.Text));
end;

Muchas gracias por tu ayuda, lo probe y funciona