Find the interest rate
Work out the yearly rate needed to turn one amount into another.
You know what you start with, what you end with and how long it takes. The calculator finds the rate that links them. Here 1,000 grows to 1,500 in 5 years.
Classic Financial II
Start on the main screen: Press 2ND then CPT (QUIT) to leave a worksheet and return to the plain calculator. ON/OFF also drops back to the standard screen and clears an error.
Enter 5 years, the 1,500 you get back as FV, and the 1,000 you put in as a negative PV.
5N1500FV1000+/-PV0PMTCompute the rate.
CPTI/Y
You should seeThe rate is about 8.45% a year.
RPN Financial 12
Start on the main screen: There is no menu to leave: the display always shows the X register. Press f then R/S (P/R) to leave program mode, and clear a pending prefix by pressing ON.
Enter the years, the amount you get back, and the amount you put in as a negative number.
5n1500FV1000CHSPV0PMTPress i to compute the rate.
i
You should see8.45
Tips
- If PV and FV have the same sign and there are no payments, no rate can fit and you get an error. One of them must be negative.