Question 750067: A tree casts a shadow 18 feet long. At the same time, a vertical rod 9 feet high casts a shadow 6 feet long. How tall is the tree? Answer by Cromlix(4381) (Show Source):
You can put this solution on YOUR website! Similar triangles
if you consider the tree and the rod as
one ratio and the tree's shadow and the
rod's shadow as the other ratio.
Then you have:
x/9 = 18/6 (x being the tree)
The sides must match like for like
Cross multiply:
6x = 162
Divide both sides by 6
x = 27
Therefore the tree is 27 feet tall.
:-)