HP 10B - Manual (Page 106)

1.
Calculate the amount of simple interest that accrues during the frac­
tional first period and add it to the loan amount. This is the new FK
You must be able to calculate the length of the odd first period as a
fraction of the whole period. (For example, a 15-day odd first
period would be 0.5 periods as.suming a whole period to be a 30-day
month.)
2. Calculate the payment using the newPy, with N equal to the
number of full periods. Use Begin mode if the number of days until
the first payment is less than 30; otherwise use End mode.
Example.
A 36-month loan for $4,500 has an annual rate of 15%. If the
first monthly payment is made in 46 days, what is the monthly payment
amount assuming 30-day months?
The odd first period in this example is 16 days.
Set to End mode. Press BlBEG/END] if begin annunciator is displayed.
Keys: Display: Description:
12a(PTYRl 12.00 Sets payments per year.
15 ilTYRl 15.00 Stores interest rate.
0 12 0 1.25 Calculates periodic
interest rate.
16 E) 30 0 0.67 Multiplies by fraction of a
period.
4500 aiSWAPi (%1 0 30.00 Calculates amount of
simple interest owed for
odd period.
0 4500 |PVl 4,530.00 Adds this simple interest
to present value.
36 0 36.00 Stores term of loan.
0 (FV) 0.00 Enters amount left to pay
after 36 payments.
(EMIl
-157.03 Calculates payment
amount.
8: Additional Examples 103