Very basic noob question about understanding class creation

After learing some procedural scripting I just started with understanding OOP and have a problem with a basic stuff like this. Why my Try.as below is not working when I type Try(1); in the main file. Output says: Type Coercion failed: cannot convert 1 to Try

package {
    public class Try {
        public function Try(some:Number) {
            some += 1;
             trace (some);
        }
    }
}