首页
登录
职称英语
Suppose that a computer password consists of four characters such that the first
Suppose that a computer password consists of four characters such that the first
游客
2024-01-12
68
管理
问题
Suppose that a computer password consists of four characters such that the first character is one of the 10 digits from 0 to 9 and each of the next 3 characters is any one of the uppercase letters from the 26 letters of the English alphabet. How many different passwords are possible?
选项
答案
156,000
解析
The description of the password allows repetitions of letters. Thus, there are 10 possible choices for the first character in the password and 26 possible choices for each of the next 3 characters in the password. Therefore, applying the multiplication principle, the number of possible passwords is(10)(26)(26)(26)= 175,760.
Note that if repetitions of letters are not allowed in the password, then the choices are not all independent, but a modification of the multiplication principle can still be applied. There are 10 possible choices for the first character in the password, 26 possible choices for the second character, 25 for the third character because the first letter cannot be repeated, and 24 for the fourth character because the first two letters cannot be repeated. Therefore, the number of possible passwords is(10)(26)(25)(24)= 156,000.
转载请注明原文地址:https://tihaiku.com/zcyy/3355382.html
相关试题推荐
Computertechnologyisadvancingsofastthatoldhardwarequicklybecomesco
Computertechnologyisadvancingsofastthatoldhardwarequicklybecomesco
Letmegiveyoua______ofhowthecomputerworks.A、demonstrationB、differenceC、
Thiskindofcomputeris______handlingallkindsofinformation.A、capabletoB、a
Inwhatnowseemsliketheprehistorictimesofcomputerhistory,theea
Inwhatnowseemsliketheprehistorictimesofcomputerhistory,theea
Theplace____________thebridgeissupposedtobebuiltshouldbe____________th
Whenyourchildissupposedtobedoinghomework,aretheychattingwiththe
Whenyourchildissupposedtobedoinghomework,aretheychattingwiththe
Whenyourchildissupposedtobedoinghomework,aretheychattingwiththe
随机试题
Concernsafewyearsagothatstudentswouldbeforcedtousestimulantsin
Althoughthetopmeninsmugglingbusinessmustworktogether,mostofasynd
Theideaoftelevision,transmittingpicturesthroughtheairoroverwires,
下列垂体瘤激素分泌过多综合征的临床表现中,错误的是A.PRL瘤女性闭经、溢乳、不
“人类的情感是音乐来源,而情感通常是由人的身体动作表现出来的,在人的身体中包括发
你班里想组织去旅游,正好你班同学家长是干这个的,你怎么办?
下列有关工程预付款的说法中,正确的有( )。A、工程预付款是承包人预先垫支的工
下列关于消防车道设置的做法,正确的有()。A.二类高层住宅建筑,沿其南北侧两个长
在征信活动中,债权人主要调查债务人的( )。A.学识水平 B.还款能力 C
儿童,10岁,游走性关节痛5年,心悸、呼吸困难2周入院。查体:T36.5℃,BP
最新回复
(
0
)