Question 1: Today is Pi Day! Pi is the ratio of a circle’s circumference to its …
- Diameter
- Radius
- Area
Answer: Diameter
Fact: Pi (π) is a special number in math, roughly equal to 3.14159, that represents the ratio of a circle’s circumference (the distance around it) to its diameter (the distance across it). No matter how big or small the circle is, this ratio always stays the same. Pi is used to calculate things like the area of a circle, the volume of a sphere, and even in complex math like calculus and physics formulas. Since pi has an infinite number of decimal places without repeating, it is often rounded for practical use.
Question 2: What kind of number is pi?
- Irrational
- Complex
- Rational
Answer: Irrational
Fact: Pi (π) is a special number that cannot be exactly written as a simple fraction, meaning it is an irrational number. Its decimal form goes on forever without ever repeating. So far, mathematicians have calculated over 202 trillion digits of pi using powerful computers, but for most real-world uses—like engineering and science—only about 15 decimal places are enough. Pi is crucial in geometry, especially for calculating the circumference and area of circles.
Question 3: What alphabet does the letter π come from?
- Cyrillic
- Armenian
- Greek
Answer: Greek
Fact: The Greek letter π was first used in math to refer to half the perimeter of a circle. In 1706, Welsh mathematician William Jones used π to represent the mathematical constant we now call pi, which is the ratio of a circle’s circumference to its diameter. The symbol became widely accepted after Swiss mathematician Leonhard Euler popularized it in the 18th century. The letter π was chosen because it comes from the Greek word ‘περιϕέρεια,’ which means circumference or periphery.