2009 AMC 12B Question 15
AMC12 · 2009 AMC 12B
Assume $0 \lt r \lt 3.$ Below are five equations for $x.$ Which equation has the largest solution $x?$
$3(1 + r)^x = 7$
$3(1 + \frac{r}{10})^x = 7$
$3(1 + 2r)^x = 7$
$3(1 + \sqrt{r})^x = 7$
$3(1 + \frac{1}{r})^x = 7$