Final answer:
There are 924 different groups of players that can be on the field at a time.
Step-by-step explanation:
To find the number of different groups of players that can be on the field at a time, we need to use the combination formula. The combination formula is given by:
C(n, r) = n! / (r!(n-r)!)
where n is the total number of players and r is the number of players on the field at a time. Substituting the given values, we get:
C(12, 6) = 12! / (6!(12-6)!) = 924
Therefore, there are 924 different groups of players that can be on the field at a time.