The equation for the standard error of the mean is the sample standard deviation divided by the square root of the sample size.

Outside the US, Pi Day should probably be July 22 (22/7)—this fraction is a surprisingly good estimate of pi. You can find the value of pi with a mass and a spring.

The idea with this less shocking build is to estimate the value of pi using the ratio of the area of a square sensor to a circular one.

Researchers are set to break the world record for the most precise value of pi, after using an advanced computer to calculate the famous constant to 62.8 trillion decimal places.