Using Scientific Notation to Estimate Quantities

“The mass of a dust particle is approximately 7.5 × 10⁻¹⁰ kg. The mass of a grain of sand is approximately 5.0 × 10⁻⁶ kg. Is the dust particle or the grain of sand larger? Explain your reasoning. The distance to Planet X is 3.2 × 10⁹ kilometers. The distance to Planet Y is 1.8 × 10¹² kilometers. Which planet is farther away? Explain your reasoning. The number of bacteria in Sample A is estimated to be 6.1 × 10⁷. The number of bacteria in Sample B is estimated to be 9.3 × 10⁴. Which sample has more bacteria? Explain your reasoning.”