Question 4337
Is the sun shining?  The easiest way to find the height of a tree or pole is to measure it's shadow, and also measure the shadow of a yard stick or other measurable height.  Then set up a proportion in the form


{{{ (height_of_pole)/(length_of_shadow) = (height_of_yardstick)/(length_of_shadow)}}}


This is a proportion with three numbers that you measured yourself and one variable (the height of the tree or pole).  It's very easy to solve for the variable using the definition of equality of fractions, also known as cross multiplying:

{{{a/b = c/d}}} is equivalent to {{{ad=bc}}}


R^2 at SCC