作业求助

linchan

Eight months ago, Louise agreed to pay Thelma $750 and $950, six and twelve
+ P8 H) T) T  l: n6 m9 z* s; E% nmonths respectively from the date of the agreement. With each payment, Louise
9 U2 {/ O. K4 a& b( S  @/ C# V, V1 Xagreed to pay interest at the rate of 9.5% pa from the date of the agreement. Louise
, ~+ u) W* P) E% L, m( _* mfailed to make the first payment and now wishes to settle her obligations with a
single payment four months from now. What payment should Thelma be willing to
( j2 r4 z6 e$ o' z! g5 Q: o1 ~! T2 G6 Aaccept 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       
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]
: [0 b, r) _" c. ]  V                                                 /(1+7.75%*8/12)           /(1+7.75%*12/12)
8 |% |9 e7 u7 e/ }5 h- I
these 3 should add up to 0, i.e. NPV at month 0 is 0.
; d# j$ M6 J; N8 D) w" J                                       
0 E$ ^) A( `3 q( LConclusion        X        =        1729.8               
" g8 I* t+ {: o, i3 Q* |; B, X                                       
5 K0 u: H0 p2 k% P% fSo, 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