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Example Questions
Example Question #1 : How To Find The Perimeter Of A Hexagon
Archimedes High School has an unusual track in that it is shaped like a regular hexagon, as above. Each side of the hexagon measures 264 feet.
Alvin runs at a steady speed of seven miles an hour for twelve minutes, starting at point A and working his way clockwise. When he is finished, which of the following points is he closest to?
Point C
Point B
Point F
Point E
Point D
Point E
Alvin runs at a rate of seven miles an hour for twelve minutes, or hours. The distance he runs is equal to his rate multiplied by his time, so, setting in this formula:
miles.
One mile comprises 5,280 feet, so this is equal to
feet
Since each side of the track measures 264 feet, this means that Alvin runs
sidelengths.
,
which means that Alvin runs around the track four complete times, plus four more sides of the track. Alvin stops when he is at Point E.
Example Question #2 : Hexagons
A circle with circumference is inscribed in a regular hexagon. Give the perimeter of the hexagon.
None of these
Below is the figure referenced; note that the hexagon is divided by its diameters, and that an apothem—a perpendicular bisector from the center to one side—has been drawn.
The circle has circumference ; its radius, which coincides with the apothem of the hexagon, is the circumference divided by :
The hexagon is divided into six equilateral triangles. One, , is divided by an apothem of the hexagon - a radius of the circle - into two 30-60-90 triangles, one of which is . Since has length 30, and it is a long leg of , then short leg has length
is the midpoint of , one of the six congruent sides of the hexagon, so
;
this makes the perimeter of the hexagon six times this, or
.