首页
登录
职称英语
The number of connections C that can be made through a switchboard to which T te
The number of connections C that can be made through a switchboard to which T te
游客
2024-01-12
20
管理
问题
The number of connections C that can be made through a switchboard to which T telephones are connected is given by the formula C = T(T-1)/2. How many more connections are possible with 30 telephones than with 20 telephones?
选项
A、435
B、245
C、190
D、45
E、10
答案
B
解析
连接有T门电话的交换机所能形成的连络数目C由公式C=T(t-1)/2给定。30门电话能比20门电话多出多少连络?
解:本题的正确答案是(B)。30门电话的连络数目:C(30)=30×(30-1)/2=435;20门电话的连络数目:C(20)=20×(20-1)=190;C(30)-C(20)=435-190=245
转载请注明原文地址:https://tihaiku.com/zcyy/3356736.html
相关试题推荐
Foranynumbersaandb,ab=ab(3-b).Ifaandabbothrepresentpositivenumbers
Thereare450birdsatasmallzoo.Thenumberofbirdsis5timesthenumberof
Forany3givennumbers,whichofthefollowingisalwaysequivalenttoaddingt
ListA,BandCmeansthelistofmultiplesofprimenumbers2,3,and5respect
Whatisthetotalnumberofdifferent5-digitintegersthatcontainallofthed
Thenumbers3,10,17,24,31and38arethefirstsixtermsofaninfinitesequ
Eachof5positivewholenumbersisatleast8.Theaverage(arithmeticmean)oft
Howmany3-digitnumbersbetween100and200haveadigitthatistheaverageof
Alisthas100numbers,theexpectationofthelistis10andthestandarddevia
Threedice,eachwithfacesnumbered1through6,weretossedontoagameboard.
随机试题
Agreenandyellowparrot,whichhunginacageoutsidethedoor,keptrepea
TheTruthabouttheEnvironmentA)Formanyenvironmentalists
廉洁从教是指教师要坚持(),发扬(),自觉抵制社会不良风气的影响,绝不利用职
下列非露天的50m长的钢筋混凝土结构,宜设置伸缩缝的是( )。A.现浇框架结构
生命伦理学的基本原则有()A.尊重人 B.有益 C.不伤害 D.
设计任务:请阅读下面学生信息和语言素材,设计20分钟的英语听力教学方案。 教案
根据《婚姻登记条例》《民法典》规定,以下说法正确的是()。A.协议离婚登记
我国中央银行公布的贷款基准利率是市场利率。()
工程质量检测单位的质量责任和义务中档案管理制度中,需要按年度统一编号的有()。
与传统融资方式相比较,项目融资的特点是()。A.风险种类少 B.前期工作量较
最新回复
(
0
)