Application Of Derivatives

A wire of length \(20 \mathrm{~m}\) is to be cut into two pieces. A piece of length \(l_{1}\) is bent to make a square of area \(A_{1}\) and the other piece of length \(l_{2}\) is made into a circle of area \(A_{2}\). If \(2 A_{1}+3 A_{2}\) is minimum then \(\left(\pi l_{1}\right): l_{2}\) is equal to :