F

RPN: Selected Examples

The following examples selected from chapter 14 (“Additional Examples”) have been converted to RPN keystrokes. These examples illustrate how to convert algebraic to RPN keystrokes in less common situations: with %, with R, and in a CFLO list.

Example: Simple Interest at an Annual Rate. Your good friend needs a loan to start her latest enterprise and has requested that you lend her $450 for 60 days. You lend her the money at 7% simple annual interest, to be calculated on a 365-day basis. How much interest will she owe you in 60 days, and what is the total amount owed?

Keys:

Display:

Description:

450 E7 % %#&.("

Annual interest.

60 *365 /

.&#*"

Actual interest for 60

 

 

days.

450 +

+..&#*"

Adds principal to get

 

 

total debt.

Example: APR for a Loan with Fees. A borrower is charged two points for the issuance of a mortgage. (One point is equal to 1% of the mortgage amount.) If the mortgage amount is $60,000 for 30 years and the interest rate is 11½% annually with monthly payments, what APR is the borrower paying?

1.Since the payment amount is not given, calculate it (PMT) first. Use the given mortgage amount (PV = $60,000) and interest rate (I%YR = 11½%).

2.To find the APR (the new I%YR), use the PMT calculated in step 1 and

276 F: RPN: Selected Examples

File name : 17BII-Plus-Manual-E-PRINT-030709

Print data : 2003/7/11