Question

Julia uses the shadow of a flagpole to estimate its height. She stands so that the tip of her shadow coincides with the tip of the flagpole’s shadow, as shown. Julia is 5 feet tall. The distance from the flagpole to Julia is 28 feet, and the distance from the tip of the shadows to Julia is 7 feet. Calculate the height of the flagpole. The diagram is not drawn to scale.

Answer 1

Answer:

Height of flagpole = 25 ft

Step-by-step explanation:

Refer the figure.

In this case ratio of height to length of shadow for Julia and Flag pole should be same.

Height of Julia = BD = 5 ft

Length of shadow of Julia = BC =  7 ft

Height of flagpole = AE = ?

Length of shadow of flagpole = AC = AB + BC =  28 +7 = 35 ft

We have

       $\frac{BC}{BD}=\frac{AC}{AE}\\\\\frac{7}{5}=\frac{35}{AE}\\\\AE=25ft$

Height of flagpole = 25 ft

Answer 2

The flag pole is 25 feet tall,
The ratio of between Julia is 5ft(height)/ 7 ft(length of shadow)
The flag pole is x/35 feet. Cross multiply 5x35=7x to get 25