Chapter 9 - Section 9.5 - Exponential and Logarithmic Equations - Exercise Set - Page 728: 105

$r=0.1685=16.85\%$

$P=1000, n=360, A=1400, t=2$ $A=P(1+\frac{r}{n})^{nt}=1000(1+\frac{r}{360})^{720}=1400$ $(1+\frac{r}{360})^{720}=1.4$ $720\log (1+\frac{r}{360})=\log 1.4$ $1+\frac{r}{360}=1.000468$ $\frac{r}{360}=0.000468$ $r=0.1685=16.85\%$