有个人去年存了1500,你希望在接下来的15年里,每年增长5%.如果现在你能在8%的时候投资这笔钱,15年后你预期能拿到多少?

题目

有个人去年存了1500,你希望在接下来的15年里,每年增长5%.如果现在你能在8%的时候投资这笔钱,15年后你预期能拿到多少?
这是我同学发给我的问题，因为我也不会回答，所以只能向百度知道求救啦~上面的题目是我同学翻译成中文的，原题如下：You are examining whether your savings will be adequate to meeting your retirement needs.You saved $1,500 last year,and you expect your annual savings to grow 5% a year for the next 15 years.If you can invest your money at 8%,how much would you expect to have at the end of the fifteenth year?希望能得到正确答案，我再加100分~呵呵

答案

首先来分析一下这道题:You are examining whether your savings will be adequate to meeting your retirement needs.(你在检查你的储蓄够不够退休用,对解题没又帮助,只是背景.)You saved $1500 last year,and you expect your annual savings to grow 5% a year for the next 15 years.(你去年存了1500美元,并且你希望之后的每年的储蓄比上一年多出5%,即如果你去年储存了100美元,今年还得在往银行里面储存105美元,而这一句是用expect来说的,就是说只是希望.)If you can invest your money at 8%,how much would you expect to have at the end of the fifteenth year?(假如你现在有能力每年储存的比前一年多8%,十五年后预期的存款是多少?)
正确的答案应该是:1500+1500*(1+8%)+1500*(1+8%)^2+...+1500*(1+8%)^15=45486.425781
上面的结果我是靠C语言编程算出来的值.以上别人的答题我差不多都看了,除了我在答题过程中提交的,没有一个上3000的,请问一个人退休后就靠不到3000元能活多久呢?!