Pi Basics
Digits of Pi
Circle Formulas
Pi in Real Life
Fun Pi Facts
100

This is the approximate value of pi rounded to two decimal places.

3.14

100

The first three digits of pi.

3.14

100

The formula for the circumference of a circle.

C = πd or C = 2πr

100

This dessert is traditionally eaten on March 14 to celebrate Pi Day.

Pie

100

Pi Day is celebrated on this date.

March 14

200

Pi represents the ratio of a circle’s circumference to this.

Diameter

200

The first five digits of pi.

3.1415

200

The formula for the area of a circle.

A = πr²

200

Pi is used to calculate the volume of this 3D shape: V = πr²h.

Cylinder

200

Albert Einstein was born on Pi Day in this year.

1879

300

The symbol used to represent pi in mathematics.

Greek Letter π 

300

The 6th digit of pi (after 3.1415).

9

300

If the radius is 5, this is the area of the circle (in terms of π).

25π

300

Engineers use pi when designing this common object with wheels.

car (car wheel)

300

This many decimal places of pi have been calculated (over this number).

1 Trillion (over 1 Trillion)

400

Pi is classified as this type of number because it never ends and never repeats.

Irrational Number

400

The next four digits after 3.14159.

2653

400

If the diameter is 10, this is the circumference (in terms of π).

10π

400

NASA uses pi to calculate the orbits of these objects.

Planets

400

Pi is used in this branch of math that studies triangles and angles. 

Trigonometry

500

This ancient mathematician first approximated pi using polygons.

Archimedes
500

The first ten digits of pi.

3.141592653

500

If a circle has a radius of 7, this is its circumference.

14π

500

Pi is essential in calculating waves in this branch of physics.

physics involving waves or trigonometry

500

This world record involves reciting thousands of digits of pi from memory.

Memorizing Digits of Pi

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