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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!

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wat.

5>117 And 15>13 give a different answer? Why?

thnxccs khen akdimy

Wow.. that adding the numbers trick is really cool!

Does anyone know where I can find that video with the adding numbers trick????

1980

1. 9. 8. 0.

you have been helping me since 4th grade. (I am in 8th grade now) you are a great help

nice

I still didn’t get it

you explain how but you dont explain how to do it in an effective way. I mean who the fuck would write out all of that out to answer every question?

How to find no. of non perfect square between n square and n+1square

Sadly real homework consist of problems far more difficult than this easy example.