Answer: The Egyptians, Babylonians, and Archimedes.
Step-by-step explanation: The Egyptians and Babylonians were the first known civilizations to use pi. At the time, Egyptians devised the approximated value of pi as 3.1605. Archimedes, however, did the first calculation of pi, with its approximate value of 3.141592 or 3.14 to make it shorter.
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