Question 469428
golden rectangle has dimensions which ratio equals the golden ratio.
The golden ratio can be derived from the Fibonacci sequence:
1,2,3,5,8,13,21... 
As the numbers increase, then the fraction of A_n/A_n-1 approaches the golden ratio
A fairly good estimate would be 21/13
{{{21/13 = 1.615}}}
So for this rectangle:
{{{10/x = 1.615}}}
Multiply by x
{{{10 = 1.615x}}}
Divide by 1.615
{{{6.19 = x}}}
Therefore length of side is 6.2 in.