HP 35s Scientific Calculator - Manual (Page 276)

17-6 Miscellaneous Programs and Equations
Part 2. What interest rate would reduce the monthly payment by $10?
Part 3. Using the calculated interest rate (6.75%), assume that you sell the car
after 2 years. What balance will you still owe? In other words, what is the future
balance in 2 years?
Note that the interest rate, I, from part 2 is not zero, so you won't get a 
  error when you calculate the new I.
Keys:
(In RPN mode)
Display: Description:
 
Displays the leftmost hart of the TVM
equation.
I

 Selects I; prompts for P.
 

 Rounds the payment to two decimal
places.


 Calculates new payment.
 
 Stores –176.89 in P; prompts for N.


 Retains 36 in N; prompts for F.


 Retains 0 in F; prompts for B.




Retains 5750 in B; calculates
monthly interest rate.
  Calculates annual interest rate.
Keys:
(In RPN mode)
Display: Description:
 
Displays leftmost part of the TVM
equation.
F

 Selects F; prompts for P.


 Retains P; prompts for I.