소모임 & 잡담
5지선다형 25문제중 찍어서 18문제 "이상" 맞출 확률좀 구해주세요.
1/10조에서 1/2000까지 다양한 수가 나와서 시망..
1/10조에서 1/2000까지 다양한 수가 나와서 시망..
![[레벨:7]](http://old.lameproof.com/modules/point/icons/default/7.gif "포인트:5105point (51%), 레벨:7/30"){kind=icon}
Dream Faller
2010.07.29 13:59:48 (*.10.66.141)
![[레벨:3]](http://old.lameproof.com/modules/point/icons/default/3.gif "포인트:896point (13%), 레벨:3/30"){kind=icon}
Rookiss /5^18*4/5^7 * nCr(25,7)
1/5^19*4/5^6 * nCr(25,6)
1/5^20*4/5^5 * nCr(25,5)
1/5^21*4/5^4 nCr(25,4)
1/5^22*4/5^3 nCr(25,3)
1/5^23*4/5^2 nCr(25,2)
1/5^24*4/5 nCr(25,1)
1/5^25
계산 결과 : 2.9 * 10^-8
1/5^19*4/5^6 * nCr(25,6)
1/5^20*4/5^5 * nCr(25,5)
1/5^21*4/5^4 nCr(25,4)
1/5^22*4/5^3 nCr(25,3)
1/5^23*4/5^2 nCr(25,2)
1/5^24*4/5 nCr(25,1)
1/5^25
계산 결과 : 2.9 * 10^-8
1/5^19*4/5^6
1/5^20*4/5^5
1/5^21*4/5^4
1/5^22*4/5^3
1/5^23*4/5^2
1/5^24*4/5
1/5^25
이걸 다 더하면 될거 같은데...