S shkspeare wants 99uai Joined Jun 11, 2003 Messages 174 Oct 16, 2004 #1 6PR = 120 find r i know its 3.. but i duno how to get it mathematically thx
C CrashOveride Active Member Joined Feb 18, 2004 Messages 1,488 Location Havana Gender Undisclosed HSC 2006 Oct 16, 2004 #2 Use the definition for permutation. i.e. in this case: 6PR = 6!/(6-R)! = 120
BillyMak Silent majority Joined Aug 20, 2004 Messages 443 Location Randwick Gender Male HSC 2004 Oct 16, 2004 #3 shkspeare said: 6PR = 120 find r i know its 3.. but i duno how to get it mathematically thx Click to expand... nPr = n!/(n-r)! :. 6Pr = 6!/(6-r)! = 120 720/(6-r)! = 120 1/(6-r)! = 1/6 (6-r)! = 6 6-r = 3 r = 3
shkspeare said: 6PR = 120 find r i know its 3.. but i duno how to get it mathematically thx Click to expand... nPr = n!/(n-r)! :. 6Pr = 6!/(6-r)! = 120 720/(6-r)! = 120 1/(6-r)! = 1/6 (6-r)! = 6 6-r = 3 r = 3
Jago el oh el donkaments Joined Feb 21, 2004 Messages 3,691 Gender Male HSC 2005 Oct 16, 2004 #4 how did you get from (6-r)! = 6 to 6-r = 3?
BillyMak Silent majority Joined Aug 20, 2004 Messages 443 Location Randwick Gender Male HSC 2004 Oct 16, 2004 #5 3! = 6 and (6-r)! = 6 :. (6-r)! = 3! 6-r = 3
