A 4.5 foot tall boy stands sovthe top of his shadow is even with the top of a flagpoles shadow if the flagpoles shadow is 34 ft. lon and the boy is stading 25 ft. away from the flagpole how tall is the flagpole?
2007-03-29 12:23:05 · 5 answers · asked by gjsfjsfk 3 in Science & Mathematics ➔ Mathematics
The answer is easy if you make a sketch of the problem.
Do this and you will see you have two similar triangles. You have the shadow of the flagpole as you base line, 34ft long. Draw a vertical line at one end of the base. The boy is standing 25ft from the flag pole. Therefore his shadow is 34 - 25 ft = 9ft long He is 4.5ft tall. Draw a line from the tip of the shadow that touches the boys head. then continue the line until it touches the vertical line of the flag pole. You now have 2 similar triangles.
The boys shadow is twice the boys height
i.e. base of small triangle = 9ft. vertical side = 4.5ft
base of large triangle = 34ft
as triangles are similar the height of the flagpole 34/2 =17ft.
2007-03-29 13:11:04 · answer #1 · answered by mad_jim 3 · 0⤊ 0⤋
This is a proportion problem.
Little boy is 4.5 feet, and his shadow must be 9 feet long (34-25).
4.5 feet boy/9 feet shadow = n feet pole/34 feet shadow
Cross multiply to solve.
2007-03-29 19:28:52 · answer #2 · answered by ecolink 7 · 0⤊ 0⤋
24 feet
2007-03-29 19:26:36 · answer #3 · answered by Anonymous · 0⤊ 0⤋
24 feet
2007-03-29 19:25:56 · answer #4 · answered by charlies angel 2 · 0⤊ 0⤋
4.5/(34 - 25) = p/34
pole height = 17 ft. high
2007-03-29 19:27:19 · answer #5 · answered by Anonymous · 0⤊ 0⤋