you wish to measure the height of a tree. you use a method where you take measurements of a yard stick and the suns shadow. the ratio of the height of the tree to the height of the yard stick (3ft) is the same the ratio of the length of the trees shadow (175ft) to the length if the yard stick shadow (7ft). find the height of the tree.

175/7 = x/3

Or, x = 175*3/7 = 75 ft

height of the tree = 75 ft.