8.EE.3 
3. Use numbers expressed in the form of a single digit times a wholenumber power of 10 to estimate very large or very small quantities, and to express how many times as much one is than the other. For example, estimate the population of the United States as 3 times 10^8 and the population of the world as 7 times 10^9, and determine that the world population is more than 20 times larger.
Lesson: Scientific notation and standard form
Checklist #2
