posted by carol .
A tree casts a shadow that measures 4 ft, At the same time, a yardstick casts a shadow that is 9 in long. How tall is the pole?
Assuming that the light comes from the same sources (in this case, the sun), the ratio of the yardstick (one yard) and its shadow (9 inches) equal the ratio of the height of the tree(pole) over 4 feet. Using that equation, convert all measures to the same units and solve.
I hope this helps. Thanks for asking.