Question

to find the value of pi, I calculated 22/7 which gace me 3.142857142857and so on, It is non repeating but why in maths it is written that 3.1415

Answer 1

Answer:

I just want to compare the 2 numbers:

22/7 = 3.142857

While pi = 3.141592

It is obvious taht these two numbers are very close each other.

Let's compare even more of them!

We are going to take the multiples of 3

3 6 9 15 18 21 24 27

And now let's add 1 to them:

4 7 10 16 19 22 25 28

And now divide them by their respective numbers that are being multiplied to 3:

4/1 = 4

7/2 = 3.5

10/3 = 3.33

13/4 = 3.25

16/5 = 3.2

19/6 = 3.1667

22/7 = 3.142857

25/8 = 3.125

28/9 = 3.111

And that's why we use the 22/7 instead of pi. It is the best approximation using just integers!

If someone have any questions about the technical stuff like why the multiples of 3 or why adding 1, feel free to answer!

Edit for the shake of all the commenteers:

Well I maybe I simplified my answer too much. To correct my mistake I should add that 22/7 is the best approximation for integers that are below 100. Why is this so important?

Many high school mathematics demand for students to be 2 decimals precise. 22/7 is good and it very easy to compute by hand in any operation compared to the other alternatives a have. Even in university we may be relaxed enough to round any number to the 3rd decimal.

So yes I oversimplified but for the shake of convenience.