Why value of pi is taken 22/7?

The question is that why did not take value of circumference other than 22 and diameter only 7?? What is the scientific reason behind this?
 
In the good old days before calculators (ie when I was at school), just about every question to do with the area or circumference of circles had circles with a radius of 7 or 14 or 21 inches. This made calculations easy because the 7s cancelled. Who else remembers this?
 
Harry_the_cat said:
In the good old days before calculators (ie when I was at school), just about every question to do with the area or circumference of circles had circles with a radius of 7 or 14 or 21 inches. This made calculations easy because the 7s cancelled. Who else remembers this?
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and your assignments were carved into wax tablets? ?
 
Sir... I need logical reason. I apperciat you also, but this is not logical and scientific answer
 
None of 22/7 nor 3.14 nor 3.1415926 (I learned a mnemonic for the last: "May I have a large container of coffee". The number of letters in each word was a digit) is equal to pi. They are approximations to pi which is an irrational number so cannot be written as a fraction or as a terminating or repeating decimal. As for "why" pi has that value, sometimes things are what they are- we don't get to choose!
 
Jamali Asif said:
Why value of pi is taken 22/7?
Click to expand...
Jamali Asif said:
The question is that why did not take value of circumference other than 22 and diameter only 7?? What is the scientific reason behind this?
Click to expand...
This approximation did not originate from taking the diameter of a circle as 7.

There are many rational approximations to pi; for any particular purpose, we can choose one that is sufficiently accurate but simple enough for our work. The approximation with the smallest numbers is 22/7; this was shown by Archimedes, using a sequence of polygons. Another is 355/113, which is quite memorable and considerably more accurate. We usually use 22/7 or 3.14 for children or for rough work, but we use a calculator's full approximation when we can.

See https://en.wikipedia.org/wiki/Approximations_of_π .
 
Harry_the_cat said:
In the good old days before calculators (ie when I was at school), just about every question to do with the area or circumference of circles had circles with a radius of 7 or 14 or 21 inches. This made calculations easy because the 7s cancelled. Who else remembers this?
Click to expand...

I remember this. ( Also the 3,4,5 triangle showed up very frequently. )

So many questions had that satisfying "cancel" moment. Writing that reminded me of a scene that I found strangely uncomfortable in the film "Good Will Hunting". I never share my cancel moments :LOL: ...

 
I was surprised to note a number of years back that 22/7 is a closer approximation to pi then 3.14 is.
 
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