Answer
$d_{\circ}=1.4m; d_i=0.48m$
Work Step by Step
We can find the object distance as follows:
$\frac{1}{f}=\frac{1}{d_{\circ}}+\frac{1}{d_i}$
We plug in the known values to obtain:
$\frac{1}{36cm}=\frac{1}{d_{\circ}}+\frac{1}{\frac{d_{\circ}}{3}}$
This simplifies to:
$d_{\circ}=4(36cm)=144.0cm=1.4m$
Now we can find the distance of the image as follows:
$d_i=\frac{d_{\circ}}{3}$
We plug in the known values to obtain:
$d_i =\frac{144cm}{3}=48cm=0.48m$
