虽然做对了，但是遇到这种看到有连续复利的题会犹豫一会，到底什么时候用e的公式什么时候直接按计算器，老师可以帮忙理一下吗？
问题如下图：
选项：
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C. 
解释：
NO.PZ2018062016000013 问题如下 You plto set a saving account for 7 years whiannuscount rate is 4% ancompounannually. Eaye$500 cash is transferreinto this account. Whis the fferenof account present value between transferring the cash the beginning anthe enof eayear? A.$500.00 B.$120.04 C.$115.42 B is correct. If the cash is transferrethe beginning, set the calculator in the BGN mo aninput tN=7, I/Y=4, PMT=500, FV=0, then PV=-3121.07. If the cash is transferrethe en set the calculator in the ENmo aninput tN=7, I/Y=4, PMT=500, FV=0, then PV=-3001.03. Therefore, the fferenbetween the two metho is 3121.07-3001.03=$120.04. 这个题目出的，每年存500，FV为什么是0？
NO.PZ2018062016000013问题如下 You plto set a saving account for 7 years whiannuscount rate is 4% ancompounannually. Eaye$500 cash is transferreinto this account. Whis the fferenof account present value between transferring the cash the beginning anthe enof eayear?A.$500.00B.$120.04C.$115.42B is correct. If the cash is transferrethe beginning, set the calculator in the BGN mo aninput tN=7, I/Y=4, PMT=500, FV=0, then PV=-3121.07. If the cash is transferrethe en set the calculator in the ENmo aninput tN=7, I/Y=4, PMT=500, FV=0, then PV=-3001.03. Therefore, the fferenbetween the two metho is 3121.07-3001.03=$120.04.老师你好，这个为什么fv是0
NO.PZ2018062016000013问题如下You plto set a saving account for 7 years whiannuscount rate is 4% ancompounannually. Eaye$500 cash is transferreinto this account. Whis the fferenof account present value between transferring the cash the beginning anthe enof eayear?A.$500.00B.$120.04C.$115.42B is correct. If the cash is transferrethe beginning, set the calculator in the BGN mo aninput tN=7, I/Y=4, PMT=500, FV=0, then PV=-3121.07. If the cash is transferrethe en set the calculator in the ENmo aninput tN=7, I/Y=4, PMT=500, FV=0, then PV=-3001.03. Therefore, the fferenbetween the two metho is 3121.07-3001.03=$120.04.老师，我在这里的理解是PV=0 求future value 求老师纠正
NO.PZ2018062016000013问题如下You plto set a saving account for 7 years whiannuscount rate is 4% ancompounannually. Eaye$500 cash is transferreinto this account. Whis the fferenof account present value between transferring the cash the beginning anthe enof eayear?A.$500.00B.$120.04C.$115.42B is correct. If the cash is transferrethe beginning, set the calculator in the BGN mo aninput tN=7, I/Y=4, PMT=500, FV=0, then PV=-3121.07. If the cash is transferrethe en set the calculator in the ENmo aninput tN=7, I/Y=4, PMT=500, FV=0, then PV=-3001.03. Therefore, the fferenbetween the two metho is 3121.07-3001.03=$120.04.做一个a aving ac不是应该PV为0吗，为什么设FV为0？
NO.PZ2018062016000013 问题如下 You plto set a saving account for 7 years whiannuscount rate is 4% ancompounannually. Eaye$500 cash is transferreinto this account. Whis the fferenof account present value between transferring the cash the beginning anthe enof eayear? A.$500.00 B.$120.04 C.$115.42 B is correct. If the cash is transferrethe beginning, set the calculator in the BGN mo aninput tN=7, I/Y=4, PMT=500, FV=0, then PV=-3121.07. If the cash is transferrethe en set the calculator in the ENmo aninput tN=7, I/Y=4, PMT=500, FV=0, then PV=-3001.03. Therefore, the fferenbetween the two metho is 3121.07-3001.03=$120.04. 题干当中说存7年钱，算先付和后付的PV的差值，那后付就是第一年年初PV没钱呀，那PV应该是0吧，先付的时候就是在第一年年初付，那PV就是500呀，那差值应该是500呀。老师我这么想的话是哪里不对吗，为什么不能这么算呢？
