15:3 is the only equivalent ratio to 20:4.
        
             
        
        
        
Step-by-step explanation:
Let A(x) be the area function of given rectangle. 
Radius of circle = 7x
Therefore, length of rectangle = 14x
Width of rectangle = 7x

Let P(x) be the Perimeter function of given rectangle. 

 
        
                    
             
        
        
        
On Oct 11: 1INR=0.04976AED
Oct 27 1INR=0.05022AED
However It's Price was highest on Oct 9 when 1AED was equal to 20.2395 INR