easy maths task ;D

by rize • 22 Oct 2010, 21:12 • Journals
hallo, and again a new very simple maths task for u (Spirea wished one ;)):

imagine a checkerboard (64 fields) and lets say, we have 8 rooks and place them randomly on 8 of 64 fields .

Whats the probability for: "no rook can beat another one".

ps: one rook can beat another one, if they ar on the same row or column

plz write the complete solution :>
Comments
26
▼
Neca 22 Oct 2010, 22:14
tbh I don't even get the question so I can't really give you a solution :s
▼
Spirea 22 Oct 2010, 22:16
playing atm, will check it soon
▼
koop 22 Oct 2010, 22:17
stopped reading after
Quoteimagine a checkboard
▼
speci 22 Oct 2010, 22:17
so 8x8 grid and a rook is just a chip that fills 1 tile?
▼
rize 22 Oct 2010, 22:25
i edited the task
Parent
▼
speci 22 Oct 2010, 22:42
Well I don't know much about probability so I don't mind that I'm not entire sure how to do this lol
Parent
▼
Puubuu 22 Oct 2010, 22:33
16/(64!-56!)=8.965*10^-14%

edited
▼
syndicate 22 Oct 2010, 22:39
ITS FRIDAY EVENING FFS I FELT LIKE A NERD STAYING AT HOME BECAUSE I HAVE TO WORK TOMORROW HOPING HERE ARE COOL GUYS AND WHAT ARE YOU DOING? MATHEMATICS AAALÖLÖLÖLÖLÖLÖ *BOOM*
▼
rize 22 Oct 2010, 22:46
actually i do other things, or do u think i make maths now? :D
Parent
▼
syndicate 22 Oct 2010, 22:48
nah i hope not ;D

image: hahahsogeil
Parent
▼
LeFrancis 22 Oct 2010, 22:48
Fortunatly there guys like MarseilleLe Francis to enjoy your night!
image: _45426081_006801539-1
Parent
▼
Deactivated7001 22 Oct 2010, 22:48
stopped reading after
Quotevery simple
▼
rize 22 Oct 2010, 22:52
:D
Parent
▼
Spirea 23 Oct 2010, 20:18
need more :) !
Parent
▼
rize 23 Oct 2010, 22:56
seems like no one besides u cares about maths tasks. Should i even make further maths journals? :)
Parent
▼
oneofTHEM 22 Oct 2010, 23:05
n(n+3)/2 + (n-2) +1
▼
Iis6r 22 Oct 2010, 23:41
chess question?
▼
Hydra 23 Oct 2010, 00:17
you there's a thing called chessboard
▼
Spirea 23 Oct 2010, 00:44
64*49*36*25*16*9*4*1 / (64!/56!)
= 8!*8! * 56! / 64!
= 9,1 * 10^-6
▼
rize 23 Oct 2010, 22:55
i really dunno if u solved it right. I know how to solve it but im to lazy to calculate it ;)
Parent
▼
Spirea 23 Oct 2010, 23:15
well what I calculated was interesting cases divided by all :P

and yeah u should make more math journals :D I want to do some math atm :) !
Parent
Back to top