问题如下图：
选项：
A. 
B. 
C. 
解释：
本题的解法我看明白了，但是经常遇到类似的题目，题干中给出了名义利率，最后先求出年实际的收益率EAR最后得到FV，想知道为何需要转EAR的原因。谢谢
菲菲_品职助教 · 2018年08月26日
同学你好，这道题题干有点问题，题干说assume compounded monthly，那么计算EAR的时候应该是（1+0.025/12）的12次方，而不是用365来算，所以这里的题干应该是compounded daily，给出的解释才是正确的做法。我们已经在后台修改题目，会尽快更新哦。
至于为什么要转换成EAR来算，因为名义年利率是对外公布的利率，比如说按照题目compounded daily，相当于每天给你算一次利息，相当于你第一天得到的利息可以加入本金计算第二天的利息，就是所谓的利滚利。一年利率等于2.5%，那么每天的利率就是2.5%/365，那么相当于一年实际的收益率为（1+2.5%/365)的365次方-1，这个就是EAR，等价年利率，等价于一年付息一次的年利率，这样进行下一步的计算就可以以年为单位，就会比较简便了。
加油~
NO.PZ2018062016000006 问题如下 Lubelieves thafter retirement she will neeabout $2 million totally for her ily expenses. present, she h$1million investment a stateannuinterest rate of 2.5%. Assuming compounily, how long es it take for Luto have enough money for retirement life? A.27.73 years B.28.07 years C.26.48 years A is correct.EAR=(1+0.025/365)365-1=0.02531$1million*(1+0.02531)N =$2million, N=27.73 years. EAR为什么是2.531，不是2.5，这里I/Y为什么需要转换
NO.PZ2018062016000006问题如下Lubelieves thafter retirement she will neeabout $2 million totally for her ily expenses. present, she h$1million investment a stateannuinterest rate of 2.5%. Assuming compounily, how long es it take for Luto have enough money for retirement life?A.27.73 yearsB.28.07 yearsC.26.48 yearsA is correct.EAR=(1+0.025/365)365-1=0.02531$1million*(1+0.02531)N =$2million, N=27.73 years.求问怎么用金融计算器计算～
NO.PZ2018062016000006问题如下 Lubelieves thafter retirement she will neeabout $2 million totally for her ily expenses. present, she h$1million investment a stateannuinterest rate of 2.5%. Assuming compounily, how long es it take for Luto have enough money for retirement life?A.27.73 yearsB.28.07 yearsC.26.48 yearsA is correct.EAR=(1+0.025/365)365-1=0.02531$1million*(1+0.02531)N =$2million, N=27.73 years.请问这题能用试错法计算吗，如果能的话要怎么算，谢谢
NO.PZ2018062016000006 问题如下 Lubelieves thafter retirement she will neeabout $2 million totally for her ily expenses. present, she h$1million investment a stateannuinterest rate of 2.5%. Assuming compounily, how long es it take for Luto have enough money for retirement life? A.27.73 years B.28.07 years C.26.48 years A is correct.EAR=(1+0.025/365)365-1=0.02531$1million*(1+0.02531)N =$2million, N=27.73 years. 为什么FV是-1不是1呢？
NO.PZ2018062016000006 问题如下 Lubelieves thafter retirement she will neeabout $2 million totally for her ily expenses. present, she h$1million investment a stateannuinterest rate of 2.5%. Assuming compounily, how long es it take for Luto have enough money for retirement life? A.27.73 years B.28.07 years C.26.48 years A is correct.EAR=(1+0.025/365)365-1=0.02531$1million*(1+0.02531)N =$2million, N=27.73 years. 同题目，这题我代入FV=2, PV=-1,I/Y=2.5,PMT=0，最后算出来的就是28.07，请问这个思路为什么错了呢？