Question

if a person 6 feet tall casts a shadow 7 feet long, and a flagpole casts a shadow 21 feet long, how tall is the flagpole? 16 ft 18 ft 27 ft, 6 in 24 ft, 6 in

Explanation:

Step1: Set up proportion

Let the height of the flag - pole be $x$ feet. Since the ratio of height to shadow length is the same for the person and the flag - pole, we have the proportion $\frac{6}{7}=\frac{x}{21}$.

Step2: Cross - multiply

Cross - multiplying gives us $7x = 6\times21$.

Step3: Solve for $x$

First, calculate $6\times21 = 126$. Then, $x=\frac{126}{7}=18$.

Answer:

B. 18 ft