Re: TVM program for HP20S Message #7 Posted by bill platt on 4 Sept 2003, 2:26 p.m., in response to message #5 by Chan Tran
Hi Chan,
Your other option is to let her use the 32siiyou put the TVM equation into the equation list, and you can solve for any variable.
Or, if you are doing the 20s route, just translate:
Most likely, you want to find out hte payments, given a set initial balance and a fixed interest rate and number of payments. So:
Given that
B = P*[1(1+I/100)^N/(I/100) ] + F*[1+(I/100)]^N
It is a simple matter to program your 20S to solve for B: Just STO the appropriate values for payment ,interest, and number of payments, and then run a program that does this equation:
LBL A
RCL P
*
(
1

(
1
+
RCL I
/
100
)
y^x
RCL N
+/
)
/
(
RCL I
/
100
)
=
+
RCL F
*
(
1
+
(
RCL I
/
100
)
)
y^x
RCL N
+/
=
RTN
for the variables, use 0 for P, 1 for I, 2 for N, and 3 for F
If you enter exactly what is here, it will run fine.
Example, a 5 year used car loan at 4.8% APR, with 100 per month, and no value at end of the loan:
B = $5324.89
so, first you store 100 in register 0, 0.4 in register 1 (that is, 4.8 / 12) and 60 in register 2, and 0 in register 3.
If you want to solve for P, you have to rearrange the equation and reenter it in the calculator. If you are lucky, it will fit along with this program, just as "label B".
There are 47 lines, and the checksum (assuming no other programs in memory) is 8A8b (leftshift show ["."] in program mode)
BTW, I entered this equation after writing it straight down, and ran it, and it worked fine. The 20S is a fine little simple algebraic machine!
Best regards,
Bill Platt
Edited: 4 Sept 2003, 2:29 p.m.
