Brahmagupta
Pi

In verse 40, he gives values of π,

12.40. The diameter and the square of the radius multiplied by 3 are the practical circumference and the area. The accurate are the square-roots from the squares of those two multiplied by ten.

So Brahmagupta uses 3 as a "practical" value of π, and 10 ≈ 3.1622 … {\displaystyle {\sqrt {10}}\approx 3.1622\ldots } as an "accurate" value of π, with an error less than 1%.
combination:two_responses