Compound Interest Formula and Natural Logarithms

AI Thread Summary
The discussion focuses on solving the compound interest formula for time (t) using natural logarithms. The formula presented is A = P(1 + r/n)^(nt). The user attempts to isolate t by taking the natural logarithm of both sides but makes an algebraic error in their calculations. A response points out the mistake, indicating the need to divide by n*ln(1 + r/n) to correctly solve for t. The user acknowledges the oversight and expresses gratitude for the clarification.
adillhoff
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Homework Statement


Solve the compound interest formula for t by using natural logarithms.


Homework Equations


A=P(1+\frac{r}{n})^{nt}


The Attempt at a Solution


I start by dividing both sides by P.
I then take the natural log of both sides and end up with

ln(\frac{A}{P})=nt * ln(1+\frac{r}{n})

I isolate t to one side by first dividing by ln(\frac{A}{P}) then by t.

I end up with t=\frac{n*ln(1+\frac{r}{n})}{ln(\frac{A}{P})}

I don't believe this is the correct answer. I can't seem to see which step I overlooked at the moment. Any help would be greatly appreciated.
 
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You made a simple algebraic mistake in the step where you solve for t. You need to divide by n*ln(1+r/n).
 
Of course. I knew I missed something simple. Thanks for the reply.
 
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