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## Pre-algebra

### Course: Pre-algebra>Unit 11

Lesson 5: Working with powers of 10

# Approximating with powers of 10

Learn how to approximate how much larger the world population was than the US population in 2014.

## Want to join the conversation?

• why area the videos easy problems and the practice questions are harder
• They're using easy questions in the videos as examples so we can get prepared for the practices, that have harder questions, more easily. But sometimes you might find the questions from videos in the pratices with the same topics!
• at why does sal use a multiplication dot operator as the numerator but a regular multiplication symbol as the other operator?
• I feel like He sometimes doesn`t always go in depth on how to
do the problem.
• how did he get the faction with 2? I don't understand where he got it from
• He simplified 7/3 by converting it from an improper fraction into a mixed number. So 7/3 is equal to 2 1/3, just in a different form. Hope this helps, it took me a minute to figure it out too.
• im khanfused
• these videos confuse me to no end
• the first thing I ever thought to myself about this video was wow! The world has really gotten smaller but still...
I won't think about it... haha