Question 126676
{{{A[1]=pi*r[1]^2}}} and {{{A[2]=pi*r[2]^2}}}.  But we are given that {{{A[1]/A[2]=25/64}}}, so we can say:


{{{(pi*r[1]^2)/(pi*r[2]^2)=25/64}}}


{{{pi/pi=1}}} so


{{{(r[1]^2)/(r[2]^2)=25/64}}}


Take the square root of both sides:
{{{sqrt((r[1]^2)/(r[2]^2))=sqrt(25/64)}}}


{{{r[1]/r[2]=5/16}}}



Which is the required ratio.