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Q:A:### Quick Answer

**According to Joy of Pi, the value of pi to 100 decimal places is expressed as 3.1415926535897932384626433832795028841971693993751058209749445923078 164062862089986280348253421170679.** Pi is an irrational number with a limitless, non-repeating decimal expansion.

Pi is a constant that represents the ratio of a circle's circumference to its diameter. Despite the constant being a ratio, it is irrational, and, therefore, a non-repeating number. It has a limitless number of decimals. As of October 2011, a Japanese mathematician and systems engineer, Shigeru Kondo, calculated pi out to its first 10 trillion digits. This broke a previous world record of 5 trillion digits calculated by Kondo just one year earlier.

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## What is pi used for?

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Full Answer >**Pi is used to find the circumference and area of a circle.**It is also used to find the volume and surface area of a sphere, cone and cylinder. Pi has applications that go beyond geometry as well, such as statistics and probability.Filed Under: - Q:
## Where did pi come from?

A:The concept of the mathematical constant pi dates back approximately 4000 years to ancient Mesopotamia. Babylonian mathematicians found that the area of a circle was figured by taking the square of the radius, multiplied by their closest approximation of pi, which was 3.

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## Why does pi not have units?

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Full Answer >**Pi does not have units because it is a number, not a measurement.**However, pi is sometimes treated like a unit when referring to angle measurements because the actual unit, radians, is a length divided by length and is therefore dimensionless.Filed Under: - Q:
## Is Pi rational?

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Full Answer >**Pi is not a rational number.**It is considered irrational. A rational number is able to be written as a fraction with integers for both the numerator and denominator.Filed Under: