Chapter 5 - Number Theory and the Real Number System - 5.6 Exponents and Scientific Notation - Exercise Set 5.6 - Page 321: 138

False. A corrected statement would be: $\dfrac{8 \times 10^{30}}{4 \times 10^{-5}} \gt 2 \times 10^{25}$

The statement is false because: $\dfrac{8 \times 10^{30}}{4 \times 10^{-5}}= \dfrac{8}{4} \times \dfrac{10^{30}}{10^{-5}} = 2 \times 10^{30-(-5)} = 2 \times 10^{35} $ A corrected statement would be: $\dfrac{8 \times 10^{30}}{4 \times 10^{-5}} \gt 2 \times 10^{25}$