# Video lesson plan for: Math Trick: Quickly Square a Number Ending in 5 in your head!

## 15th-Century Italian Art: Greek, Roman & Classical Influences

* Whiteboard required ** This activity is teacher paced

How to square any numbers in your head - fast mental math trick here: https://www.youtube.com/watch?v=GEuyDHMG0jY There is barely any calculation needed to mentally find the square a number that ends in five. How fast? The square of 45 is 1225; The square of 85 is 7225; the square of 115 is 12125; the square of 1095 is 1188125....as fast as I can type them I answer them! The trick is this to faster squaring.... Say we have 65 squared. Get the number that is not 5 ( that is 6) and multiply it by the next number after it (7). Then just write 25 on the end. So 6 x 7 = 42, our answer is 4225. Really. Simple 'eh?

Tagged under: Fast,math,trick,square,Speed,faster---calculator,calculator,vedic,vedic math,homeschool,home,school,homeschool math,Homeschooling,calculation

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