作业求助

linchan

Eight months ago, Louise agreed to pay Thelma $750 and $950, six and twelve
months respectively from the date of the agreement. With each payment, Louise
# Z: w  d9 Z. N; g- Lagreed to pay interest at the rate of 9.5% pa from the date of the agreement. Louise
* o( R7 h5 ~% I/ n. v2 ^' kfailed to make the first payment and now wishes to settle her obligations with a
9 _# s$ v% y6 B: S  O1 a9 ^* m) Qsingle payment four months from now. What payment should Thelma be willing to
accept if money can earn 7.75%? （最好有过程）

littledognancy

Suppose Intr is annually compounded                                       
$ J8 y5 P( r" Y- k$ a1 p# p                Month 0        Mon. 8                  Mon. 12
. U$ @% y. N2 N2 lCash Principal        X        -750                  -950       
Cash Intr (Should Pay)                -X*9.5%*8/12          -(X-750)*9.5%*4/12               
PV at mon 0        X        -[750+X*9.5%*8/12]          -[950+(X-750)*9.5%*4/12]
8 P  c4 J+ Q) E! D' P- Q                                                 /(1+7.75%*8/12)           /(1+7.75%*12/12)

these 3 should add up to 0, i.e. NPV at month 0 is 0.
% \/ n, V( ?& Y6 W- g6 Q$ N                                       
Conclusion        X        =        1729.8               
6 A3 D7 c! M" ~                                       
So, Initial borrowing was        1730        *(1+7.5%)        1859.5        approx.         $1,860
* e3 n' i+ r# y' s& Y  O) F

littledognancy

Finance 学得不好所以不知道做得对不对。。。看着办吧~ 也许有用。

linchan

对了，答案是$1856.32