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On the HP30b, is it possible to enter non-integer P / YR values and thus not get an ERROR message? At HP, is there any way to convert decimal or fractional numbers to whole numbers (C / YR and P / YR)?

Currently, I find interest rates equivalent, either by a program on the HP30b, or by the traditional method. Is there a possibility to do this without a program?

Example: I have the rate 1.8% bimonthly (2 months) and I want the equivalent effective rate for quarter (3 months).

With the program I do:
1.8 I / YR 3 INPUT 2 ÷ N SHIFT PRGM =

Or manually:
1.8 I / YR PV = 1 N = 1 FV =? (= -1,0002) 2 INPUT 3 ÷ N I / YR =?

Answer: 2.7%

Sorry for the question and errors in English (I use Google Translate), but I'm starting on the HP30b. Still thanks and happy holidays!

Do you have the Owner's Manual for your 30b?

There is a copy you can download here:

https://literature.hpcalc.org/official/h...-ug-en.pdf

1.8% bi-monthly rate to quarterly (3-months) effective rate:

1.018 ^ (3/2) = 1.027121138             // effective quarterly rate = 2.7121138%

One way to do it manually is to pretend that 1.8% is an annual rate compounded yearly for 6 years, then determine the interest rate that would produce the same future value in 4 years:

(01-01-2021 01:58 PM)ijabbott Wrote: [ -> ]One way to do it manually is to pretend that 1.8% is an annual rate compounded yearly for 6 years, then determine the interest rate that would produce the same future value in 4 years

No need to pretend: (I/Yr) ÷ (P/Yr) = I/P

By setting P/Yr = 1, whatever entered into I/Yr is I/P (interest rate per period).

So, the code can also interpret as first getting APY (FV = -1.11297822601 → APY ≈ 11.2978%),
then convert to quarterly rate (I/P ≈ 2.7121%, P = 3 months)

(12-31-2020 07:43 PM)FabioBrasil Wrote: [ -> ]On the HP30b, is it possible to enter non-integer P / YR values and thus not get an ERROR message?

This also answered OP question.

Example: P/Yr = 3.14, I/Yr = 6% is equivalent to P/Yr = 1, I/P = I/Yr = 6%/3.14

Thank you all