Excavations at
Harappa,
Mohenjo-daro and other sites of the
Indus Valley Civilization (IVC) have uncovered evidence of the use of "practical mathematics". The people of the IVC manufactured bricks whose dimensions were in the proportion 4:2:1, considered favorable for the stability of a brick structure. They used a standardized system of weights based on the ratios: 1/20, 1/10, 1/5, 1/2, 1, 2, 5, 10, 20, 50, 100, 200, and 500, with the unit weight equaling approximately 28 grams (and approximately equal to the English ounce or Greek uncia). They mass-produced weights in regular
geometrical shapes, which included
hexahedra,
barrels,
cones, and
cylinders, thereby demonstrating knowledge of basic
geometry.
[20]
The inhabitants of Indus civilization also tried to standardize measurement of length to a high degree of accuracy. They designed a ruler—the
Mohenjo-daro ruler—whose unit of length (approximately 1.32 inches or 3.4 centimetres) was divided into ten equal parts. Bricks manufactured in ancient Mohenjo-daro often had dimensions that were integral multiples of this unit of length.
[21][22]
Mehrgarh, a
Neolithic IVC site, provides the earliest known evidence for
in vivo drilling of human teeth, with recovered samples dated to 7000-5500 BCE.
[23]