Originally Posted by

**HallsofIvy** I get a slightly different answer. I used the fact that $\displaystyle \frac{0.97^x}{0.96^x}= \left(\frac{0.97}{0.96}\right)^x= 1.0104^x$ so that $\displaystyle 1.0104^x= 1.2105$. Now take the logarithm of both sides: $\displaystyle x log(1.0104)= log(1.2105)$ so $\displaystyle 0.00500x= 0.08296$ and the [tex]x= \frac{0.08296}{0.00500}= 16.6, so the answer is 1996+ 17= 2013 rather than 2015. What was the answer in your text? It might be just a matter of round off error.