此题为何要用后付年金计算？而不是先付年金方式？问题如下图：
选项：
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B. 
C. 
解释：
NO.PZ2017092702000016 问题如下 A sports car, purchasefor £200,000, is financefor five years annurate of 6% compounmonthly. If the first payment is e in one month, the monthly payment is closest to: A.£3,847. B.£3,867. C.£3,957. B is correct,“the first payment is e in one month”是第一笔付款在第一个月的意思（t=1），所以是个后付年金问题。后付年金模式下，PV=-200,000, N=12*5， I/Y=6/12，FV=0 CPT PMT=3866.56 为什么不需要先计算EAR（6.17%），然后再代入PV=-200000，N=5*12，I/Y=6.17/12，FV=0，求PMT？
NO.PZ2017092702000016 问题如下 A sports car, purchasefor £200,000, is financefor five years annurate of 6% compounmonthly. If the first payment is e in one month, the monthly payment is closest to: A.£3,847. B.£3,867. C.£3,957. B is correct,“the first payment is e in one month”是第一笔付款在第一个月的意思（t=1），所以是个后付年金问题。后付年金模式下，PV=-200,000, N=12*5， I/Y=6/12，FV=0 CPT PMT=3866.56 为什么让PV=0,FV=200000算出来的不对的呢
NO.PZ2017092702000016问题如下A sports car, purchasefor £200,000, is financefor five years annurate of 6% compounmonthly. If the first payment is e in one month, the monthly payment is closest to: A.£3,847. B.£3,867. C.£3,957. B is correct,“the first payment is e in one month”是第一笔付款在第一个月的意思（t=1），所以是个后付年金问题。后付年金模式下，PV=-200,000, N=12*5， I/Y=6/12，FV=0 CPT PMT=3866.56 如果是按照月度复利计息，为什么不是（年利率6%+1）开12次方根再减1，按照这个计算下来是0.486755%，，，而是直接用年利率6%除以12个月等于0.5%？不考虑按月复利计息吗？
NO.PZ2017092702000016问题如下A sports car, purchasefor £200,000, is financefor five years annurate of 6% compounmonthly. If the first payment is e in one month, the monthly payment is closest to: A.£3,847. B.£3,867. C.£3,957. B is correct,“the first payment is e in one month”是第一笔付款在第一个月的意思（t=1），所以是个后付年金问题。后付年金模式下，PV=-200,000, N=12*5， I/Y=6/12，FV=0 CPT PMT=3866.56 这个e是预先支付的意思，为什么不能理解为0时刻支付？
NO.PZ2017092702000016 £3,867. £3,957. B is correct, “the first payment is e in one month”是第一笔付款在第一个月的意思（t=1），所以是个后付年金问题。 后付年金模式下，PV=-200,000, N=12*5， I/Y=6/12，FV=0 CPT PMT=3866.56 如果是先付，题目一般会怎么描述？
