If a 36-inch yardstick casts a 21-foot shadow, how tall is a building whose shadow is 168 feet?
February 20th, 2023
The sun must be very low in the sky, as a 24foot building would cast the 168 foot shadow.
Always be careful that the units of your calculation are consistent. It is a common trick in word problems to see if you are attentive.
It is best to stay in feet rather than inches in this problem.
The 36 inches is equal to 3 ft.
I prefer to just use a proportion to solve:
##3/ 21## = ##x/168## Using cross products we calculate x = 24 ft.