1. Since each of the top 4 players receives $37 500, the order in which they finish does not matter. You simply have to be in the top 4 to receive the same amount. This is an example of combinations, specifically "16 choose 4". From the formula we get:
                            
   The money can be distributed in 1820 ways if each of the top four receives $37 500 

2. Since the amount you receive depends on your position in the top 4, order matters. This is thus an example of permutations, specifically "16 permute 4". From the formula we get:
                            

The money can be distributed in 43 680 ways if the amount received depends on the position in the top 4, order matters.