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
68
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://www.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
Ifthatideawaswrong,theprojectisboundtofail,______goodalltheother
Asshewalkedroundthehugedepartmentstore,Edithreflectedhowdifficult
LastweekIwenttothetheatre.Ihadaverygoodseat.Theplaywasvery(
[originaltext]W:Thereisaseatbyawindow.AndIamsohappythatwecouldb
TheLibraryofCongressisAmerica’snationallibrary.Ithas【B1】______ofbo
Forsomeeducators,thereisnothingwrongwithfunandgames.Agroupcalle
患者男。YZ706_159_5.gif缺失,余留牙正常,口底距舌侧龈缘的距离为4
220V的蓄电池组整体绝缘电阻低于(____)时应进行更换100kΩ$;
按《港口工程地基规范》(JTJ250—1998)要求,验算港口建筑物饱和软黏土地
人在每一瞬间,将心理活动选择了某些对象而忽略了另一些对象。这一特点指的是注意的(
最新回复
(
0
)