The tablet on the left, YBC 7302, shows a diagram of a circle with the
numbers `3`, `9` and `45`. The `45` represents
the area of the circle, while `3` is the circumference. The usual
rule for computing the area of a circle in Old Babylonian mathematics is
A=C^2/12, or rather `A=5C^2` as `5` is the reciprocal of
`12`.

The second tablet shows a diagram of a trapezoid, a very common figure
in Old Babylonian mathematics, again with numbers representing the lengths
of sides and the area. The base and side are inscribed with `2,20`,
the top with `2`. The area is obtained by a standard procedure in
Old Babylonian mathematics of `5,3,20 = 2,20x(2,20+2)x30`.

Both of these tablets were originally published by Neugebauer and Sachs in Mathematical Cuneiform Texts.

I thank Professor W.W. Hallo for permission to use the images of the tablets.

Go to Mesopotamian Mathematics.

Last modified: 6 June 2001

Duncan J. Melvilledmelville@stlawu.edu