Applications
this application) and the add-on interest rate are known. The amount of monthly payment can be calculated also for any given principal. The formula uses the constant storage location, therefore, any value stored there will be destroyed when the final key (the one that triggers the result) is pressed. The information is entered as follows:
1 Enter the number of months, press n.
2 Enter the annual add-on interest rate, press i.
3 Press i again to obtain the annual percentage rate.
4 Press x y to obtain monthly payment factor.
5 Enter principal, press × to obtain amount of monthly payment.
Sample Case: What is the true rate of interest (annual percentage rate) on an 18 month, 5 % add-on loan? What would be the monthly payment on a principal of $1500?
Solution
 Enter:  See Displayed:  
 
18 n 5 i i   
  9.27
  % annual percentage rate
 
x y   
  0.06
  monthly payment factor (0.059722 if shown with 6 decimal places)
 
1500 ×   $
  89.58
  monthly payment amount
Accrued Interest
This calculation finds the amount of accrued interest on both a 360and 365-day basis when the number of periods (days only in this application), interest rate, and principal (present value) are known. The formula uses the constant storage location, therefore, any value stored there will be destroyed when the final key (the one that triggers the result) is pressed. The information is entered as follows:
1 Enter number of days, press n.
2 Enter annual interest rate, press i.
3 Enter principal, press PV.
4 Press   PMT (INTR) to obtain the amount of interest on a 360-day basis.
5 Press x y to obtain the amount of interest on a 365-day basis.
Sample Case: What is the amount of accrued interest due on $450 for 50 days at 7%, figured on a 360/ 365-day basis?
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