GMAT Math : Calculating the perimeter of a polygon
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Example Questions
Example Question #1 : Calculating The Perimeter Of A Polygon
What is the perimeter of a hexagon?
1) Each side measures 10 cm
2) The hexagon is regular.
EACH statement ALONE is sufficient.
Statement 1 ALONE is sufficient, but Statement 2 alone is not sufficient.
Statements 1 and 2 TOGETHER are not sufficient.
BOTH statements TOGETHER are sufficient, but neither statement ALONE is sufficient.
Statement 2 ALONE is sufficient, but Statement 1 alone is not sufficient.
Statement 1 ALONE is sufficient, but Statement 2 alone is not sufficient.
The perimeter is the sum of the measures of the sidelengths.
Knowing that the hexagon is regular only tells you the six sides are congruent; without the measure of any side, this does not help you.
Knowing only that each of the six sides measures 10 cm is by itself enough to calculate the perimeter to be
The answer is that Statement 1 is sufficient, but not Statement 2.
Example Question #2 : Polygons
Note: Figure NOT drawn to scale
What is the perimeter of the above figure?
Assume all angles shown in the figure are right angles.
Not enough information is given to answer the question.
This figure can be seen as a smaller rectangle cut out of a larger one; refer to the diagram below.
We can fill in the missing sidelengths using the fact that a rectangle has congruent opposite sides. Once this is done, we can add the lengths of the sides to get the perimeter:
Example Question #1 : Polygons
What is the perimeter of a rectangle with a length of 
The perimeter 
Example Question #2 : Calculating The Perimeter Of A Polygon
What is the perimeter of a right triangle with a base of 
Not enough information provided
In order to find the perimeter 
We could have also noted that 
Now that we have all three side lengths, we can calculate 
Example Question #2 : Calculating The Perimeter Of A Polygon
What is the perimeter of an octagon with equal side lengths of 
Starting with the knowledge that we are dealing with an octagon, an 8-sided figure, we calculate the perimeter 
Example Question #1 : Calculating The Perimeter Of A Polygon
The smallest pair of congruent sides are 5 inches long each.
The other two congruent sides are 1.5 times bigger than the smallest sides.
The last side is twice the length of the smallest sides.
What is the perimeter of 
A pentagon is a 5 sided shape. We are given that two sides are 5 inches each.
Side 1 = 5inches
Side 2 = 5 inches
The next two sides are each 1.5 times bigger than the smallest two sides.
Side 3 =Side 4= 7.5 inches
The last side is twice the size of the smallest side,
Side 5 =10 inches
Add them all up for our perimeter:
5+5+7.5+7.5+10=35 inches long
Example Question #2 : Calculating The Perimeter Of A Polygon
One side of a regular dodecagon has a length of 
A regular dodecagon is a polygon with twelve sides of equal length, so if one side has a length of 
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