工程经济学一道题~

来源:百度知道 编辑:UC知道 时间:2024/05/18 12:52:23
The three alternatives described below are available for supplying a community water supply for the next 50 years when all economic lives, as well as the period of analysis, terminates.

Cost Project A Project B Project C
Construction Cost
Year 0 $20,000,000 $10,000,000 $15,000,000
Year 20 0 $10,000,000 $12,000,000
Year 35 0 $10,000,000 0
Maintenance Cost
Years 1 - 20 $70,000 $40,000 $60,000
Years 21 - 35 $80,000 $70,000 $80,000
Years 36 - 50 $90,000 $90,000 $90,000

Determine which project is preferred using the present worth method. Assume an interest rate of 4.5%.

以前没学过 这是另一门课的题。用present worth method 来选择是什么意思? 麻烦知道的人告诉我详细的计算过程啦,谢谢~
排版有点乱, 费用是3个工程排在一起 工程a的建设费用是0年$20,000,000,后面2个阶段都是0. 工程b是3个阶段开始都投资$10,000,000,工程c是第35年是0.

应该是分别求三个工程的净现值NPV,画出相应的现金流量图就OK了

我列出工程a的计算式子,其他两个类似的,最后比较三个NPV的大小,去最小的那个。
NPV(a)=20,000,000+70,000*(P/A,4.5%,20)+80,000*(P/A,4.5%,15)*(P/F,4.5%,20)+90,000*(P/A,4.5%,15)*(P/F,4.5%,35)