作业求助

linchan

Eight months ago, Louise agreed to pay Thelma $750 and $950, six and twelve
5 g1 y( e6 y/ H% Q+ }( qmonths 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
failed to make the first payment and now wishes to settle her obligations with a
+ v/ ~! u9 S5 d1 y# ]) v5 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                                       
3 _4 m' E' R" {) S! b2 A0 a                Month 0        Mon. 8                  Mon. 12
Cash Principal        X        -750                  -950       
Cash Intr (Should Pay)                -X*9.5%*8/12          -(X-750)*9.5%*4/12               
2 P; s8 V. ^0 M6 [9 YPV at mon 0        X        -[750+X*9.5%*8/12]          -[950+(X-750)*9.5%*4/12]
' w1 u* l5 ]" I+ f/ q$ c                                                 /(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.
3 k& U  j% s# ^, P, ^4 Y! {" V                                       
* I" [; P1 ^- A. @1 p( F5 NConclusion        X        =        1729.8               
                                       
So, Initial borrowing was        1730        *(1+7.5%)        1859.5        approx.         $1,860

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