Chapter 8 - Section 8.1 - The Square Root Property and Completing the Square - Exercise Set - Page 594: 76

$10$%

Since, $A=(1+r)^t$ Plug the values in the given expression. Such as $A=(1+r)^t$ or, $2420=2000(1+r)^2$ This implies that $r=\sqrt {\dfrac{2420}{2000}}-1$ or, $r=0.1$ and Hence, $r$ can be written as: $r = 10$%