Find perimeter of various shapes. Practice this lesson yourself on KhanAcademy.org right now: https://www.khanacademy.org/math/pre-algebra/measurement/perimeter/e/perimeter_1?utm_source=YT&utm_medium=Desc&utm_campaign=PreAlgebra Watch the next lesson: https://www.khanacademy.org/math/pre-algebra/measurement/perimeter/v/comparing-area-and-perimeter?utm_source=YT&utm_medium=Desc&utm_campaign=PreAlgebra Missed the previous lesson? https://www.khanacademy.org/math/pre-algebra/measurement/perimeter/v/introduction-to-perimeter?utm_source=YT&utm_medium=Desc&utm_campaign=PreAlgebra Pre-Algebra on Khan Academy: No way, this isn't your run of the mill arithmetic. This is Pre-algebra. You're about to play with the professionals. Think of pre-algebra as a runway. You're the airplane and algebra is your sunny vacation destination. Without the runway you're not going anywhere. Seriously, the foundation for all higher mathematics is laid with many of the concepts that we will introduce to you here: negative numbers, absolute value, factors, multiples, decimals, and fractions to name a few. So buckle up and move your seat into the upright position. We're about to take off! ... https://www.youtube.com/watch?v=sJmLjUj_h68 Note: All Khan Academy content is available for free at (www.khanacademy.org)

Practice this lesson yourself on KhanAcademy.org right now: https://www.khanacademy.org/math/arithmetic/addition-subtraction/sub_borrowing/e/subtraction_4?utm_source=YT&utm_medium=Desc&utm_campaign=Arithmetic Watch the next lesson: https://www.khanacademy.org/math/arithmetic/addition-subtraction/sub_borrowing/v/alternate-mental-subtraction-method?utm_source=YT&utm_medium=Desc&utm_campaign=Arithmetic Missed the previous lesson? https://www.khanacademy.org/math/arithmetic/addition-subtraction/sub_borrowing/v/borrowing-once-example-1?utm_source=YT&utm_medium=Desc&utm_campaign=Arithmetic Arithmetic on Khan Academy: So you're ready to have some arithmetic fun? You've come to the right spot! It's the first "official" math topic and chalked full of fun exercises and great videos which help you start your journey towards math mastery. We'll cover the big ones: addition, subtraction, multiplication, and division, of course. But we don't stop there. We'll get into negative numbers, absolute value, decimals, and fractions, too. Learning math should be fun, and we plan on having some with you. Ready to get started? About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We've also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content. ... https://www.youtube.com/watch?v=8_fT1BsTmt4 Note: All Khan Academy content is available for free at (www.khanacademy.org)