All GMAT Math Resources
Example Questions
Example Question #3 : Calculating The Area Of A Square
A square, a regular pentagon, and a regular hexagon have the same sidelength. The sum of their perimeters is one mile. What is the area of the square?
The square, the pentagon, and the hexagon have a total of 15 sides, all of which are of equal length; the sum of the lengths is one mile, or 5,280 feet, so the length of one side of any of these polygons is
feet.
The square has area equal to the square of this sidelength:
Example Question #4 : Calculating The Area Of A Square
A square and a regular pentagon have the same perimeter. The length of one side of the pentagon is 60 centimeters. What is the area of the square?
The regular perimeter has sidelength 60 centimeters and therefore perimeter centimeters. The square has as its sidelength centimeters and area square centimeters.
Example Question #2 : Calculating The Area Of A Square
Six squares have sidelengths 8 inches, 1 foot, 15 inches, 20 inches, 2 feet, and 25 inches. What is the sum of their areas?
The areas of the squares are the squares of the sidelengths, so add the squares of the sidelengths. Since 1 foot is equal to 12 inches and 2 feet are equal to 24 inches, the sum of the areas is:
square inches
Example Question #1 : Calculating The Area Of A Square
What polynomial represents the area of Square if ?
As a square, is also a rhombus. The area of a rhombus is half the product of the lengths of its diagonals, one of which is . Since the diagonals are congruent, this is equal to half the square of :
Example Question #2 : Calculating The Area Of A Square
Given square FGHI, answer the following
If square represents the surface of an ancient arena discovered by archaeologists, what is the area of the arena?
This problem requires us to find the area of a square. Don't let the story behind it distract you, it is simply an area problem. Use the following equation to find our answer:
is the length of one side of the square; in this case we are told that it is , so we can solve accordingly!
Example Question #9 : Calculating The Area Of A Square
Note: Figure NOT drawn to scale
Refer to the above figure, which shows Square and Square . and Square has area 49. Give the area of Square .
Square has area 49, so each of its sides has as its length the square root of 49, or 7. Each side of Square is therefore a hypotenuse of a right triangle with legs 1 and , so each sidelength, including , can be found using the Pythagorean Theorem:
The square of this, which is 37, is the area of Square .
Example Question #1 : Calculating The Area Of A Square
Note: Figure NOT drawn to scale
Refer to the above figure, which shows Square and Square . and Square has area 25. Give the area of Square .
Square has area 25, so each side has length the square root of 25, or 5.
Specifically, , and, as given, .
Since is a right triangle with hypotenuse and legs and , can be found using the Pythagorean Theorem:
The area of is
Since all four triangles, by symmetry, are congruent, all have this area. the area of Square is the area of Square plus the areas of the four triangles, or .
Example Question #401 : Gmat Quantitative Reasoning
Note: Figure NOT drawn to scale
Refer to the above figure, which shows Square and Square . The ratio of to is 13 to 2. What is the ratio of the area of Square to that of Square ?
To make this easier, assume that and - the reasoning generalizes. Then Square has sidelength 15 and area . The sidelength of Square , each side being a hypotenuse of a right triangle with legs 2 and 13, is
.
The square of this, 173, is the area of Square .
The ratio is .
Example Question #171 : Geometry
Note: Figure NOT drawn to scale
Refer to the above figure, which shows Square and Square . The ratio of to is 7 to 1.
Which of these responses comes closest to what percent the area of Square is of that of Square ?
To make this easier, assume that and ; the results generalize.
Each side of Square has length 8, so the area of Square is 64.
Each of the four right triangles has legs 7 and 1, so each has area ; Square has area four times this subtracted from the area of Square , or
.
The area of Square is
of that of Square .
Of the five choices, 80% comes closest.
Example Question #13 : Squares
The perimeter of a square is the same as the circumference of a circle with area 100. What is the area of the square?
The formula for the area of a circle is
.
If the area is 100, the radius is as follows:
The circle has circumference times its radius, or
This is also the perimeter of the square, so the sidelength of the square is one-fourth this, or
The area of the square is the square of this, or