241.One project ,A needs 12hours to finish it alone,while B needs 15hours to finish it alone.After A and B working together for an hour ,then A works an hour,B works an hour.A and B turn down like this .So how many hours does the project need?
来源:学生作业帮助网 编辑:作业帮 时间:2024/05/20 03:58:47
241.One project ,A needs 12hours to finish it alone,while B needs 15hours to finish it alone.After A and B working together for an hour ,then A works an hour,B works an hour.A and B turn down like this .So how many hours does the project need?
小学的题.
翻译如下:一项工程,A独自完成需要12小时,B独自完成需要15小时.
A和B共同工作1小时后,A独自工作一小时,然后B独自工作一小时
这样轮流下去,完成这项工程需要多少个小时?
A的工作效率是1/12,B的工作效率是1/15,也就是说A、B一小时完成的分别占总工程的1/12和1/15
这样A、B共同工作一小时完成的量是1/12+1/15=3/20
那么就还剩下17/20的工程量让A、B来轮流完成
惊奇地发现17/20=5*(1/12+1/15)+1/10
也就是说A、B这样轮流了5次之后 再轮回到A来做再做总工程的1/10就可以完成了
所以需要的时间是:1+2*5+(1/10)/(1/12)=12.2
不是一个整数,答案是11.2小时。
顺便说一下,如果还有这样的问题还可以来找我
a one man or one woman research project是什么意思?Each individual in this country should be forming a one man or one woman research project.a one man or one woman research project是什么意思?
a/an与one哪个比较正式?一个是不定冠词,一个应该是基数名词吧?比如a project还是one project比较正式一点呢?
he is working on the math project this______week.A.all B.whole C.one D.next
one such 还是 a such__ suuch project is underway.填a 还是 the 好__ such project is underway.填a 还是 the 好,为什么?
do a project
in a housing project
241.One project ,A needs 12hours to finish it alone,while B needs 15hours to finish it alone.After A and B working together for an hour ,then A works an hour,B works an hour.A and B turn down like this .So how many hours does the project need?
英语翻译The course development team consisted of four faculty members,one project coordinator,and one web instructional designer,all from a large university system in a southern state.
project
project
project
do a project和make a project有什么区别
A project for the projects.
on a project by project basis 何意?
PMP题,选择并请给个理由,The software development project is not going well.There are over 30 stakeholders,and no one can agree on the project objectives.One stakeholder believes the project can achieve a 30 percent improvement while another b
Three people who work full time are to work together on a project,but their total time on the projThree people who work full time are to work together on a project,but theirtotal time on the project is to be equivalent to that of only one person work
the head engineer is in__the project A.his charge ofB.the charge ofC.charge ofD.one's charge选什么 为什么
the head engineer is in__the project A.his charge ofB.the charge ofC.charge ofD.one's charge选什么为什么