aplikasi menghitung lembar fotocopy dari delphi

mohon kritik dan saranya

procedure TForm1.Button2Click(Sender: TObject); begin Edit1.Clear; Edit2.Clear; Edit3.clear; Edit4.Clear; Edit5.clear; end; procedure TForm1.FormCreate(Sender: TObject); begin Edit1.Clear; Edit2.Clear; Edit3.clear; Edit4.Clear; Edit5.Clear; end; procedure TForm1.Button1Click(Sender: TObject); var nilai,x:Real; begin if (RadioButton1.Checked=false) and (RadioButton2.Checked=false) then   begin   Application.MessageBox('pilih pelanggan atau tidak','::info:::',MB_ICONINFORMATION);   end   else if (Edit1.text)=''  then   begin   Application.MessageBox('lengkapi datax','info');   end   else if RadioButton1.Checked then   begin   Edit3.text:=IntToStr(StrToInt(Edit1.text)*StrToInt(Edit2.text));   x:=0.2;   nilai:=x*StrToFloat(Edit3.Text);   Edit4.Text:=FloatToStr(nilai);   end else if RadioButton2.Checked then   begin   Edit3.Text:=IntToStr(StrToInt(Edit1.Text)*StrToInt(Edit2.text));   x:=0.05;   nilai:=x*StrToFloat(Edit3.text);   Edit4.Text:=FloatToStr(nilai);   end end; procedure TForm1.Button3Click(Sender: TObject); begin CLOSE; end; procedure TForm1.Button4Click(Sender: TObject); var kembalian:Real; begin kembalian:=StrToInt(Edit4.Text)-StrToInt(Edit5.Text); Label7.Caption:=FloatToStr(kembalian); end; end.