Find the height of the pole if the shadow of a boy 6 ft. tall is 3 ft. and the shadow of the pole is 2 1/3 yards.

First of all, we need to convert 2 1/3 yards into feet. 
2 1/3 = 7/3 yard. Since a yard has 3 feet, we multiply this by 3 and we get that 2 1/3 yards equal 7 feet.
Now we move on to proportions.
If the shadow of a boy 6 feet tall produces the shadow of 3 feet, we need to see which height can produce a shadow of 7 feet.

6: 3 = x : 7
3x = 42
x = 14

The height of the pole is 14 feet.