英文跟数学好的请进,关于概率的问题
Q1:Twentyfivehockeyplayersareavailableforselectionforthestateteam.Theteamwillhavesixdefenceplayersandfiveforwardplayers.
(i)Howmanyteamsofelevenplayersarepossiblefromthegroupoftwentyfive?
(ii)Howmanyteamscanbeselectediffiveforwardsarechosenfromthetenavailableandsixdefenceplayersarechosenfromthefifteenavailable?
Q2Amongagroupof40first-yearstudentsatacollegecampushalfofthemgraduatedfromhighschooltheyearbefore,whiletheremaindertooka“gap-year”graduatingfromhighschooltwoyearsbefore.Seventypercentofthefirst-yearstudentsaremaleandsevenofthefemalestudentsgraduatedfromhighschooltheyearbefore.
(i)Findtheprobabilitythatarandomlyselectedfirst-yearstudentisbothfemaleand
tooka“gap-year”.
(ii)Whatistheprobabilitythatgivenarandomlyselectedstudenttooka“gap-year”thestudentismale?
Q3(i)Acardisdrawnfromanordinarydeckofplayingcardsthathasbeenshuffledanumberoftimes.Whatistheprobabilitythatthecarddrawnisaredcardoraface
card(jack,queenorking)?
(ii)Whenanunbiasedsix-sideddieisrolledfivetimeswhatistheprobabilityofhavingonlyoddnumbersresult?
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