Chapter 4 - Polynomials - 4.2 Negative Exponents and Scientific Notations - 4.2 Exercise Set - Page 245: 107

$2.47\times10^{8}$

Using the laws of exponents and the concepts of scientific notation, the given expression, $ (3.8\times10^9)(6.5\times10^{-2}) $, simplifies to \begin{array}{l} (3.8)(6.5)\times10^{9+(-2)} \\\\= 24.7\times10^{7} \\\\= 2.47\times10^{8} .\end{array}