Microsoft has fixed a decade-old issue in the Windows Calculator, according to a report by Softpedia.
The issue is known as the “square root of perfect square” bug, and resulted in incorrect answers in certain scenarios.
“Windows 10 Redstone 5 build 17639 is the one bringing this bugfix,” stated Softpedia.
The report stated that you can replicate the bug by opening the calculator app, calculating the square root of 4, then subtracting 2.
The answer should be 0, but the Windows Calculator “sometimes gives the wrong answer, due to what Microsoft claims to be arbitrary precision arithmetic library”.