UnityEngine.Rect' does not have a visible constructor that matches the....

Ok, so i made this script and i came up with an error that i cant seem to fix. UnityEngine.Rect' does not have a visible constructor that matches the argument list (float, int, int)

I looked up other solutions but i still couldnt find the problem

the error is on 72,28

 var Planks : int;
 var Sticks : int;
 var Stone : int;
 var Rocks : int;
 var WoodWall : Transform;
 var WoodHatchet : Transform;
 var StoneHatchet : Transform;
 var Knife : Transform;
 var Menu = false;
 var look01 : MouseLook;
 var look02 : MouseLook;
 var charController : CharacterController;
 
 function Start () 
 {
     look01 = gameObject.GetComponent(MouseLook);
     look01 = GameObject.Find("MainCamera").GetComponent(MouseLook);
     charController = gameObject.GetComponent(CharacterController);
 }
 
 function Mining(Rock : int) 
 {
     Stone += Rocks;    
 }
 
 function TreeMining(Wood : int) 
 {
     Sticks += Wood;
 }
 
 function Update () 
 {
     if(Menu == false)
     {
       look01.enabled = true;
       look02.enabled = true;
       charController.enabled = true;
     }
 //} NOT NEEDED
     if(Menu == true)
     {
       look01.enabled = false;
       look02.enabled = false;
       charController.enabled = false;
     }
 //} NOT NEEDED
     if (Input.GetKeyDown(KeyCode.Tab))
     {
       Menu = !Menu;
     }
     //New one needed here
 }
 
 function WeaponKnife()
 {
 if(Sticks >= 2)
         {
         if(Stone >=3)
                 {
                     Knife.active = true;
                     Stone -= 3;
                     Sticks -= 2;
                     Menu = !Menu;
                 }
         }
 }
 
 function OnGUI ()
 {
     if(Menu == true)
     {
     if (GUI.Button(Rect(Screen.width*0.5-50, 200-20,100-40),"Knfie"))
             {
             WeaponKnife();
             }
     }
 }