Question 840244
Circumference of a circle is {{{C=2*pi*R}}}.
{{{C[2]/C[1]=R[2]/R[1]=2/5}}}
{{{5R[2]=2R[1]}}}
{{{R[1]=(5/2)R[2]}}}
{{{R[1]=(5/2)(16)}}}
{{{R[1]=40}}}