  Let 0<m<(n-2)/n, n>2, $\alpha=(2\beta +\rho)/(1-m)$ and
$\beta>m\rho/(n-2-mn)$ for some constant $\rho>0$. Suppose v is a radially
symmetric symmetric solution of $\frac{n-1}{m}\Delta v^m+\alpha v+\beta
x\cdot\nabla v=0$, v>0, in $R^n$. When m=(n-2)/(n+2), the metric
$g=v^{4/(n+2)}dx^2$ corresponds to a locally conformally flat Yamabe shrinking
gradient soliton with positive sectional curvature. We prove that the solution
$v$ of the above nonlinear elliptic equation has the exact decay rate
$\lim_{r\to\infty}r^2v(r)^{1-m}=\frac{2(n-1)(n(1-m)-2)}{(1-m)(\alpha
(1-m)-2\beta)}$.
