We are asked to express r in terms of A, P, and t.
We first divide both sides of the equation by t, which gives us
,
then, dividing both sides by P, we have
.
Swap the sides:
Finally subtracting 1 from both sides gives us
.
We first divide both sides of the equation by t, which gives us
then, dividing both sides by P, we have
Swap the sides:
Finally subtracting 1 from both sides gives us