A geometry error in homework has persisted for 4,000 years: what is inscribed on the Babylonian tablet?

The Babylonian clay tablet, housed at the University of Oxford, essentially serves as an ancient math homework assignment that is 4,000 years old, reports LiveScience.

The tablet was discovered during archaeological excavations in 1931. Researchers believe that a student used the tablet as a "notebook" for calculating the area of a triangle. The Babylonian made a mistake in their calculations, which has persisted for nearly 4,000 years.

The diameter of the small tablet is just 8.2 cm, and it features a right triangle with three sets of numbers inscribed in cuneiform. Each set of numbers is along one of the two sides, indicating the triangle's length and height, as well as its area.

Along the top line (height) of the triangle, the student wrote 3.75, while the vertical line (base) is marked as 1.875. These values imply that the area of the triangle should be 3.5156. However, the student incorrectly calculated it as 3.1468.

Several similar tablets with homework assignments have been found in Kish and Babylon, which were rightly considered centers of early mathematical education. Some tablets, on the reverse side, contain remarks from teachers.

In ancient Babylon, mathematical education began to flourish alongside the major empires of the world. Algebra and geometry were invented around 3000 BC in Sumer, as emerging civilizations needed methods for calculating taxes, trade, commerce, and creating calendars.

In Babylonian mathematics, much like in modern mathematics, a base-60 counting system was adopted, for example, 60 seconds in a minute, 60 minutes in an hour. The ancient Babylonians also mastered the Pythagorean theorem nearly a century before the ancient Greek philosopher discovered that the sum of the squares of the two legs of a right triangle equals the square of the hypotenuse.

According to archaeologists, such tablets with homework in geometry and algebra indicate significant cultural development. The knowledge that people accumulated and transmitted at some point transitioned from memorization to written information.

This crucial shift occurred around 3500 BC in Kish and was so foundational that it is often compared to the transition from paper to digital records in the 20th century.

As a reminder, scientists deciphered a 3,000-year-old Babylonian tablet. The stone tablet is considered the oldest map ever found in history.