Beejank using Casting out 9 and Casting out 11- A Comparative Analysis
DOI:
https://doi.org/10.31305/rrjiks.2026.v3.n1.013Keywords:
Beejank, Ancient Mathematics, Casting out 9, Casting out 11Abstract
Beejank is one of the basis operations used in ancient Indian mathematics for verification of arithmetic operations. The popular definition of Beejank quotes it as the process of summing its digits repeatedly until a single digit is obtained. However, we dive in depth and explore two popular approaches of calculating Beejank- Casting out 9 and Casting out 11. The detailed understanding of both the approaches is discussed. Further, comparison of casting out 9 and 11 is done for various arithmetic operations and identify the suitability for verification of results. Constraints of both the approaches have been summarized.
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