Vedic / Quicker / Shortcut Math ⇒ Topic : Choose a nice middle number

Angel
 
When subtracting two numbers in my head that are fairly near to each other, I like to choose a nice looking number that comes between the numbers e.g. 100, 200, 5000 etc. If you know someone was born in 1979 and you want to find out how old they are, you have: 2008 – 1979 Well, a nice number between these is the number 2000. First of all, work out the differences between 2000 and 2008, and 1979 and 2000, and then add the differences up The difference between 2000 and 1979 is 21 The difference between 2000 and 2008 is 8 Add the differences: 21 + 8 = 29  
 
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