height of tree = 65 ft
length of shadow = 13 ft
Let draw a diagram to illustrate the question effectively
The proportion can be set up below
[tex]\begin{gathered} \frac{65}{20}=\frac{13}{x} \\ \text{cross multiply} \\ 65x=260 \\ x=\frac{260}{65} \\ x=4\text{ ft} \end{gathered}[/tex]
Th shadow will be 4 ft. do you
