All GMAT Math Resources
Example Questions
Example Question #5 : Calculating The Length Of The Side Of A Square
Two squares in the same plane have the same center. The length of one side of the smaller square is 10; the area of the region between the squares is 60. Give the length of one side of the larger square.
Let be the length of one side of the larger square. Then the larger square has area ; the smaller square has area . The area of the region between them, 60, is their difference:
Example Question #1 : Calculating The Length Of The Side Of A Square
Two squares in the same plane have the same center. The length of one side of the larger square is 10; the area of the region between the squares is 60. Give the length of one side of the smaller square.
Let be the length of one side of the smaller square. Then the smaller square has area ; the larger square has area . The area of the region between them, 60, is their difference:
Example Question #191 : Geometry
What is the area of a trapezoid with a height of 7, a base of 5, and another base of 13?
Example Question #192 : Geometry
A circle can be circumscribed about each of the following figures except:
A regular hexagon
A triangle
A triangle with sides 30, 40, 50.
Each of the figures given in the other choices can have a circle circumscribed about it.
A regular pentagon
Each of the figures given in the other choices can have a circle circumscribed about it.
A circle can be circumscribed about any triangle regardless of its sidelengths or angle measures, so we can eliminate the two triangle choices.
A circle can be circumscribed about any regular polygon, so we can eliminate those two choices as well.
The correct choice is that each figure can have a circle circumscribed about it.
Example Question #2 : Calculating The Area Of A Quadrilateral
What is the area of a quadrilateral on the coordinate plane with vertices ?
As can be seen from this diagram, this is a parallelogram with base 8 and height 4:
The area of this parallelogram is the product of its base and its height:
Example Question #3 : Calculating The Area Of A Quadrilateral
What is the area of a quadrilateral on the coordinate plane with vertices ?
As can be seen in this diagram, this is a trapezoid with bases 10 and 5 and height 8.
Setting in the following formula, we can calculate the area of the trapezoid:
Example Question #5 : Calculating The Area Of A Quadrilateral
Note: Figure NOT drawn to scale
What is the area of Quadrilateral , above?
Quadrilateral is a composite of two right triangles, and , so we find the area of each and add the areas. First, we need to find and , since the area of a right triangle is half the product of the lengths of its legs.
By the Pythagorean Theorem:
Also by the Pythagorean Theorem:
The area of is .
The area of is .
Add the areas to get , the area of Quadrilateral .
Example Question #3 : Calculating The Area Of A Quadrilateral
What is the area of the quadrilateral on the coordinate plane with vertices ?
The quadrilateral formed is a trapezoid with two horizontal bases. One base connects (0,0) and (9,0) and therefore has length ; the other connects (4,7) and (7,7) and has length . The height is the vertical distance between the two bases, which is the difference of the coorindates: . Therefore, the area of the trapezoid is
Example Question #6 : Calculating The Area Of A Quadrilateral
What is the area of the quadrilateral on the coordinate plane with vertices .
The quadrilateral is a trapezoid with horizontal bases; one connects and and has length , and the other connects and and has length . The height is the vertical distance between the bases, which is the difference of the -coordinates; this is . Substitute in the formula for the area of a trapezoid:
Example Question #5 : Other Quadrilaterals
What is the area of the quadrilateral on the coordinate plane with vertices ?
The quadrilateral is a parallelogram with two vertical bases, each with length . Its height is the distance between the bases, which is the difference of the -coordinates: . The area of the parallelogram is the product of its base and its height: