Question

which ratio is known as golden ratio

Answer 1

 two quantities are in the golden ratio if their ratio is the same as the ratio of their sum to the larger of the two quantities

Answer 2

Golden ratio is a number which is approximately equal to the value 1.618
it is also considered that if two mathematical quantities have the same ratio as the ratio of their sum to the larger of the two mathematical quantities.
it is denoted by the Greek letter phi