Question 308515
Let x= height of the tree


Set up the ratio:
{{{(Height)/(Shadow)=5/12=x/54}}}


Since {{{a/b=c/d}}} means {{{ad=bc}}},
{{{5/12=x/54}}} means {{{5*54=12x}}}

{{{270=12x}}}
{{{x=270/12}}}= 22.5 feet.


Dr. Robert J. Rapalje, Retired