作业求助

linchan

Eight months ago, Louise agreed to pay Thelma $750 and $950, six and twelve
months respectively from the date of the agreement. With each payment, Louise
agreed to pay interest at the rate of 9.5% pa from the date of the agreement. Louise
2 o* K; C1 H$ p0 x1 P2 Mfailed to make the first payment and now wishes to settle her obligations with a
2 Z: G3 d  ~% N6 ~' c, ~5 i/ Jsingle 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                                       
                Month 0        Mon. 8                  Mon. 12
Cash Principal        X        -750                  -950       
( Z8 z0 E% t/ Q6 V. ZCash Intr (Should Pay)                -X*9.5%*8/12          -(X-750)*9.5%*4/12               
! o3 O1 i+ p# a3 DPV at mon 0        X        -[750+X*9.5%*8/12]          -[950+(X-750)*9.5%*4/12]
                                                 /(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.
                                       
Conclusion        X        =        1729.8               
; F$ T. l9 \. U+ p) A' S                                       
So, Initial borrowing was        1730        *(1+7.5%)        1859.5        approx.         $1,860
3 l0 z; c% G# B# W' x* K

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