Loads of errors with classes: 1067 implicit coercion 118 illegal assignment

Question

Hi
I have a main.fla and the two classes below VirtualGarage and VirtualCar. Main has VirtualGarage as its class which in turn works with VirtualCar. The code seems quite good but I get these errors. If anybody could help
Cheers
//VirtualGarage class
package
public class VirtualCar extends VirtualGarage
var carSpeed:Number;
var carColour:String;
var carPrice:String;
var car;
public function VirtualCar(speed,colour,price)
this.carSpeed = speed;
this.carColour = colour;
this.carPrice = price;
//VirtualCar class
package
import VirtualCar;
public class VirtualGarage
private var newVirtualCar;
public function VirtualGarage()
newVirtualCar:VirtualCar = new VirtualCar(20,"red",30000);
trace(newVirtualCar.speed;

Answer 1

Hi - thank you very much.
I know have the concept pretty well learnt. Although I find the statement class extends something to be ambiguous - it doesn't actually extend it - it inherits methods and properties from it. That's why I was so confused.
However, I still have an error after modifying certain parts of code
Main is now VirtualGarage.fla
                  VirtualGarage.as - class document
                  VirtualCar.as - another class
Both .as docs reside in a folder called "garage" therefore there package name is garage.
I get these errors 1067 implicit coercion... and 1188 illegal assignment to VirtualCar
VirtualGarage.as
package garage
import flash.display.Sprite;
public class VirtualGarage extends Sprite
private var newVirtualCar:VirtualCar;
public function VirtualGarage()
newVirtualCar:VirtualCar = new VirtualCar("red"); //throws the error - 1067 implicit coercion... and 1188 illegal assignment to VirtualCar
VirtualCar.as
package garage
public class VirtualCar //extends what? ie: a movieclip that calls it or the main class
public var colour:String;
public function VirtualCar(newColour)
colour = newColour;