golden ratio: Quick Facts

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Facts

Also Known As	divine proportion • golden section • 1.618 • golden mean • extreme and mean ratio

Photos

Golden ratio diagram showing segments a and b, where phi equals a divided by b and a plus b divided by a, approximately 1.618; a golden rectangle is divided into blue a and red b sections.

Diagram titled Golden spiral with rectangles showing segments a and b, the formula (a + b)/a = a/b = 1.618033..., and colored nested rectangles with a white spiral.

Price chart with Fibonacci levels shown.

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Topics

golden rectangle number game pentagram number irrational number ratio perfect number zero cross ratio significant figures e scientific notation amicable numbers real number transfinite number prime

Equations written on blackboard

Numbers and Mathematics

barometer. Antique Barometer with readout. Technology measurement, mathematics, measure atmospheric pressure

Fun Facts of Measurement & Math