"Discovery: Decimal Point Found in 1440s Merchant's Notes"
Math historian Glen Van Brummelen discovered a decimal used to indicate tenths of a number in a 15th-century treatise, challenging the belief that German mathematician Christopher Clavius was the first to use decimals in a 1593 treatise. The treatise by Venetian merchant Giovanni Bianchini, using a base-10 system, marked a significant advancement in calculations, potentially influencing Clavius's work. This finding sheds new light on the history of decimals and their early usage in mathematical calculations.