Ошибки [Error] Unit1.pas(40): Incompatible types

unit Unit1;
 
interface
 
uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;
 
type
  TForm1 = class(TForm)
    Label1: TLabel;
    Edit1: TEdit;
    Label2: TLabel;
    Button1: TButton;
    Edit3: TEdit;
    Label3: TLabel;
    Edit2: TEdit;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;
 
var
  Form1: TForm1;
 
implementation
 
{$R *.dfm}
 
procedure TForm1.Button1Click(Sender: TObject);
 var S,p,ku:Real;
begin
 
 
 p:=StrToInt( Edit1.Text);
 ku:=StrToInt( Edit2.Text);
 s:= StrToInt(Edit3.Text);
 if p= [1..3,13,14] then
  s:= ku*270*1
 else if p=[4..7] then
s:=ku*270*2.5
 else if p=[8,9] then
  s:= ku*270*1.8
  else if p=[10..12] then
  s:=ku*270*1.5
   else ShowMessage('Помилка');
 
end;
 
 
end.

var S,p,ku:integer;

var p:byte;

if p in [4..7]