Select 4 unique numbers from 4 to 6
        Total possible combinations (ways)
        
If order does not matter (e.g. most lottery numbers): 15
If order matters (e.g. pick3 numbers, permutations, lock combinations, pin-codes): 81
            
                If order does not matter (e.g. most lottery numbers): 15
If order matters (e.g. pick3 numbers, permutations, lock combinations, pin-codes): 81



