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Julian Rhind-Tutt is 48 years old (birthdate: July 20, 1968).
The earliest known textually evidenced approximations of PI date from around 1900 BC. They are found in the Egyptian Rhind Papyrus.
August Eisenlohr has written: 'Ein mathematisches Handbuch der alten Aegypter' -- subject(s): Egyptian Mathematics, Papyrus Rhind
Riddles originated from well they were made by "Rhind Mathematical Papyrus.
The earliest documentation of who invented the square root was the Rhind Mathematical Papyrus which shows how the Egyptians extracted square roots around 1650 BC.
It is not known. The Rhind Papyrus describes how the area of a circle is related to pi where pi was estimated as (4/3)4 ≈ 3.1605 (approx). The Rhind Papyrus dates from around 1700 BCE. So either very ancient people used pi = 3 or else they were later people who were dogmatically required to use pi = 3.
Al Rhind was born in 1896.
John Rhind died in 1889.
John Rhind was born in 1836.
David Rhind died in 1883.
David Rhind was born in 1808.