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## #1 2013-02-05 16:52:49

Banon
Guest

### Periodic compound interest

In periodic interest if I know everything except number of  compoundings per year,how do I find it?

## #2 2013-02-05 19:25:09

bob bundy
Moderator

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### Re: Periodic compound interest

hi Banon,

I'm assuming you mean 'if I know all the variables except n, how do I work it out?'

http://www.mathsisfun.com/money/compoun … l#periodic

Half way down the page is the formula for this.

Bob

You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

## #3 2013-02-05 22:03:21

Banon
Guest

### Re: Periodic compound interest

Sorry,but i couldn't find any formula for n there.There is the formula Fv=Pv(1+r/n)^(nt) but i don't know how to solve that expression for n.

## #4 2013-02-05 22:32:33

bobbym

Online

### Re: Periodic compound interest

Hi Banon;

You can not always solve for any variable you want. In this case I do not think you can get n by itself on the left.

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #5 2013-02-06 00:26:09

bob bundy
Moderator

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### Re: Periodic compound interest

hi Banon,

Arhh yes! Good point.

You could solve it graphically like this;

using

http://www.mathsisfun.com/data/function … p;ymax=1.2

I've chosen r = 0.05 and you have to have x instead of n.

You can put y = FV/PV as the second graph and zoom in on the point where the line cuts the curve.

Bob

You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei