A group of 8 friends want to play doubles tennis. How many different ways can the group be divided into 4 teams of 2 people?	Select the correct option:
A) 420 B) 2520 C) 168 D) 90 E) 105
C28∗C26∗C24∗C22/4!=105 , we are dividing by 4! (factorial of the # of teams) as the order of the teams does not matter. If 8 people are - 1, 2, 3, 4, 5, 6, 7, 8, then (1,2)(3,4)(5,6)(7,8) would be the same 4 teams as (5,6)(7,8)(1,2)(3,4), as we don't have team #1, team #2, ...   You can think about this in another way.   For the first person we can pick a pair in 7 ways;   For the second one in 5 ways (as two are already chosen);   For the third one in 3 ways (as 4 people are already chosen);   For the fourth one there is only one left.   So we have   7*5*3*1= 
<gadget id="calculator">  7*5*3*1</gadget>
<output>105</output>
105   ANSW105R:105
<result>E</result>
A group of 8 friends want to play doubles tennis. How many different ways can the group be divided into 4 teams of 2 people?