Pi, represented by the Greek letter π, is a crucial mathematical constant used to calculate the circumference of a circle. It is approximately equal to 3.14159 and is defined as the ratio of a circle’s circumference to its diameter. Archimedes first estimated Pi around 250 BC, getting its value up to seven digits.

**National Pi Day** is celebrated every year on March 14th. This date, 3/14, matches the first three digits of Pi: 3.14. Larry Shaw, a staff member at the Exploratorium in San Francisco, founded Pi Day in 1988. In 2009, the US House of Representatives recognized Pi Day officially. People celebrate with fun activities like pie-eating contests and Pi-recitation competitions. In November 2019, UNESCO also declared Pi Day as the International Day of Mathematics.

## GK Questions on Pi

**Ques 1. Name the scientist who was born on Pi Day?**

A. Diophantus

B. Archimedes

C. Einstein

D. Euclid

**Ans: C**

**Ques 2. Which of the following statement is correct about Pi?**

A. It is non-repeating decimal value

B. It is non-terminating decimal value

C. It is repeating and terminating decimal value

D. It is non-repeating, non-terminating decimal value

**Ans: D**

**Ques 3. Pi (π) is a mathematical constant that represents the ratio of what to what in a circle?**

A. Area to radius

B. Diameter to radius

C. Circumference to diameter

D. Radius to height

**Ans: C**

**Ques 4. What is the value of Pi?**

A. 3.14159

B. 3.14358

C. 3.14258

D. 3.14289

**Ans: A**

**Ques 5. Who is considered the father of Pi Day?**

A. Albert Einstein

B. Larry Shaw

C. Isaac Newton

D. Pythagoras

**Ans: B**

**Ques 6. What fraction is commonly used as an approximation for pi?**

A. 3/4

B. 22/7

C. 1/2

D. 3/5

**Ans: B**

**Ques 7. Pi consists of how many digits?**

A. 9 digits

B. 10 digits

C. 12 digits

D. Infinite

**Ans: D**

**Ques 8. Who has calculated the area of a circle by taking the value of Pi equal to 3?**

A. Babylonians

B. Archimedes

C. Both A and B

D. Neither A nor B

**Ans: A**

**Ques 9. When Pi Day is celebrated around the world?**

A. 14 Feb

B. 14 March

C. 14 April

D. 15 March

**Ans: B**

**Ques 10. Pi algorithm up to 5 correct decimal places was invented by which Chinese mathematician?**

A. Zu Chongzhi

B. Liu Hui’s

C. Shen kuo

D. Pan Jianwei

**Ans: B**

**Ques 11. Who first described the familiar value of Pi which we are considering now?**

A. Euclid

B. Liu Hui’s

C. Zu Chongzhi

D. None of the above

**Ans: A**

**Ques 12. Who is credited with the first calculation of Pi?**

A. Isaac Newton

B. Archimedes

C. Pythagoras

D. Albert Einstein

**Ans: B**

**Ques 13. Who was the first to use the Greek letter pi (π) to denote the constant?**

A. Leonhard Euler

B. William Jones

C. Mayans

D. Papyrus

**Ans: B**

**Ques 14. What is the numerical value of Pi (π)?**

A. 3.14

B. 2.71

C. 4.13

D. 1.86

**Ans: A**

**Ques 15. What does the mathematical constant π represent?**

A. Ratio of a circle’s radius to its circumference

B. Ratio of a circle’s diameter to its circumference

C. Ratio of a circle’s diameter to its area

D. Ratio of a circle’s circumference to its diameter

**Ans: D**

**Ques 16. Who has calculated the circumference of the earth and considered the value of Pi = 22/7?**

A. Archimedes

B. John Machin’s

C. Aryabhatta

D. None of the above

**Ans: C**

**Ques 17. In what year did Google release a Google Doodle to honor Pi Day?**

A. 2008

B. 2009

C. 2010

D. 2011

**Ans: C**

**Ques 18. Which film directed by Darren Aronofsky features the mathematical constant pi?**

A. Inception

B. The Matrix

C. Pi

D. Interstellar

**Ans: C**

**Ques 19. Pi is commonly used in which field of mathematics?**

A. Algebra

B. Calculus

C. Trigonometry

D. All of the above

**Ans: C**

**Ques 20. What is the date for Pi Approximation Day?**

A. March 22nd

B. July 22nd

C. August 22nd

D. September 22nd

**Ans: B**

**Ques 21. What is the relationship between the circumference (C) and diameter (d) of a circle, represented by Pi?**

A. C = d/π

B. C = πd

C. C = πd^2

D. C = d^2/π

**Ans: B**