Question

At your school, the building is 20 feet tall, a tree's height is 252 inches, and the flagpole is 6 yards high. Which of the three objects casts the longest shadow?

Answer 1

First, all the heights have to be converted to similar units, say feet.

Therefore,
Building= 20 feet
Tree = 252*0.083333 = 21 feet
Flagpole = 6*3 = 18 feet

The tallest of the three is the tree and thus should cast the longest shadow. However, it should be noted that at exactly noon when the sun is overhead, all the three will have equal length of shadow (that is, 0 feet long).