Maths tricks for fast calculation - 1 views

• 
  #1 mayuri06296 on 10 Nov 21

   

  Division by 5 :
  
  What is 50 by 5 = 10 that's easy but what is 3421 by 5.
  It's not that easy to calculate in mind right?
  What is the sum of all even numbers from 0 to 10.
  
  
  Now, there are 4 even numbers between 0 and 10.
  
  Which are 2, 4, 6 and 8.
  
  Let's visualize these numbers.
  
  So, what have I got here is a rectangle of 4 into 5 which is 20. And guess the formula i.e. n + 1.
  
  
  Now try it with odd numbers. It's not exactly this formula but it's something different.
  
  i.e. square numbers
  
  The sum of the first n odd number is n2.
  
  Let's remember 5 is 10/2 so,
  How about if we first divide this by 10
  So, 3421 divided by 10 is 342.1 and now I can multiply this by 2 . I've got 684.2. Wasn't that quick enough?
  
  https://www.englishmaths.in/2021/11/maths-tricks-for-fast-calculation.html

   

  <div class="cArrow"> </div><div class="cContentInner">Division by 5 : <br /> <br /> What is 50 by 5 = 10 that's easy but what is 3421 by 5. <br /> It's not that easy to calculate in mind right? <br /> What is the sum of all even numbers from 0 to 10. <br /> <br /> <br /> Now, there are 4 even numbers between 0 and 10. <br /> <br /> Which are 2, 4, 6 and 8. <br /> <br /> Let's visualize these numbers. <br /> <br /> So, what have I got here is a rectangle of 4 into 5 which is 20. And guess the formula i.e. n + 1. <br /> <br /> <br /> Now try it with odd numbers. It's not exactly this formula but it's something different. <br /> <br /> i.e. square numbers <br /> <br /> The sum of the first n odd number is n2. <br /> <br /> Let's remember 5 is 10/2 so, <br /> How about if we first divide this by 10 <br /> So, 3421 divided by 10 is 342.1 and now I can multiply this by 2 . I've got 684.2. Wasn't that quick enough? <br /> <br /> <a href="https://www.englishmaths.in/2021/11/maths-tricks-for-fast-calculation.html" rel="nofollow" target="_blank">https://www.englishmaths.in/2021/11/maths-tricks-for-fast-calculation.html</a></div>

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