In how many ways can 12 people divide into

Question

Two equal groups?

Three equal groups?

Answer 1

n = 12, r = 6

 

₁₂P₆ if order does matter (12!)/(6!) = 66,5280

 

₁₂C₆  if order doesn't matter   (12!)/((6!)(6!)) = 924 

 

n=12, r = 4

 

₁₂P₄ if order does matter (12!)/(4!) = (12!)/(8!) = 11,880

 

₁₂C₄ if order doesn't matter (12!)/((8!)(4!)) = 495

 

A²