Hii!

I have this other piece of practice work that I don't understand.

The method I do understand is for calculating the final amount:

The amount to start with is 21 860

The interest is 8.5 %

The years are 7

I know that you must do:

$\displaystyle P+ (i . P . n )$

= $\displaystyle 21 860+ (0.085 . 21 860 . 7)$

That's easy.

What I'm stuck on is:

Final amount is 8 775

Interest is 7%

Years are 5

CALCULATE THE AMOUNT YOU STARTED WITH.

What would I do?

Thanks!