All GRE Math Resources
Example Questions
Example Question #1 : How To Find The Length Of The Side Of A Parallelogram
Using the parallelogram shown above, find the length of side
A parallelogram must have two sets of congruent/parallel opposite sides. Therefore, this parallelogram must have two sides with a measurement of and two base sides each with a length of Since the perimeter and one base length is provided in the question, work backwards using the perimeter formula:
, where and are the measurements of adjacent sides.
Thus, the solution is:
Example Question #1342 : Gre Quantitative Reasoning
A parallelogram has a base of . The perimeter of the parallelogram is . Find the sum of the two adjacent sides to the base.
A parallelogram must have two sets of congruent/parallel opposite sides. This parallelogram must have two sides with a measurement of and two base sides each with a length of . In this question, you are provided with the information that the parallelogram has a base of and a total perimeter of . Thus, work backwards using the perimeter formula in order to find the sum of the two adjacent sides to the base.
, where and are the measurements of adjacent sides.
Thus, the solution is:
Example Question #1343 : Gre Quantitative Reasoning
A parallelogram has a base of . An adjacent side to the base has a length of . Find the perimeter of the parallelogram.
A parallelogram must have two sets of congruent/parallel opposite sides. Therefore, this parallelogram must have two sides with a measurement of and two base sides each with a length of To find the perimeter of the parallelogram apply the formula:
, where and are the measurements of adjacent sides.
Thus, the solution is:
Example Question #25 : Quadrilaterals
A parallelogram has a base of . The perimeter of the parallelogram is . Find the length for an adjacent side to the base.
A parallelogram must have two sets of congruent/parallel opposite sides. Therefore, this parallelogram must have two sides with a measurement of and two base sides each with a length of . To solve for the missing side, work backwards using the perimeter formula:
, where and are the measurements of adjacent sides.
Thus, the solution is:
Example Question #1341 : Gre Quantitative Reasoning
A quadrilateral has equal sides, each with a length of .
Quantity A: The area of the quadrilateral.
Quantity B: The perimeter of the quadrilateral.
The relationship cannot be determined.
The two quantities are equal.
Quantity A is greater.
Quantity B is greater.
The relationship cannot be determined.
We are told that the shape is a quadrilateral and that the sides are equal; beyond that, we do not know what specific kind of kind of quadrilateral it is, outside of the fact that it is a rhombus. The perimeter, the sum of the sides, is .
If this shape were a square, the area would also be ; however, if the interior angles were not all equivalent, the area would be smaller than this.
The relationship cannot be determined.
Example Question #151 : Plane Geometry
A rectangle has an area of 48 and a perimeter of 28. What are its dimensions?
2 x 24
0.25 x 192
1 x 48
6 x 8
16 x 3
6 x 8
We can set up our data into the following two equations:
(Area) LH = 48
(Perimeter) 2L + 2H = 28
Solve the area equation for one of the two variables (here, length): L = 48 / H
Place that value for L into ever place you find L in the perimeter equation: 2(48 / H) + 2H = 28; then simplify:
96/H + 2H = 28
Multiply through by H: 96 + 2H2 = 28H
Get everything on the same side of the equals sign: 2H2 - 28H + 96 = 0
Divide out the common 2: H2 - 14H + 48 = 0
Factor: (H - 6) (H - 8) = 0
Either of these multiples can be 0, therefore, consider each one separately:
H - 6 = 0; H = 6
H - 8 = 0; H = 8
Because this is a rectangle, these two dimensions are the height and width. If you choose 6 for the "height" the other perpendicular dimension would be 8 and vice-versa. Therefore, the dimensions are 6 x 8.
Example Question #31 : Quadrilaterals
The length of a rectangle is three times its width, and the perimeter is . What is the width of the rectangle?
For any rectangle, , where , , and .
In this problem, we are given that (length is three times the width), so replace in the perimeter equation with :
Plug in our value for the perimeter, :
Simplify:
Example Question #1 : Rectangles
The area of a rectangle is . Its perimeter is . What is the length of its shorter side?
We know that the following two equations hold for rectangles. For area:
For perimeter:
Now, for our data, we know:
Now, solve the first equation for one of the variables:
Now, substitute this value into the second equation:
Solve for :
Multiply both sides by :
Solve as a quadratic. Divide through by :
Now, get the equation into standard form:
Factor this:
This means that (or ) would equal either or . Therefore, your answer is .
Example Question #1 : How To Find The Length Of The Diagonal Of A Rectangle
Given Rectangle ABCD.
Quantity A: The length of diagonal AC times the length of diagonal BD
Quantity B: The square of half of ABCD's perimeter
Quantity A is greater.
The relationship cannot be determined from the information given.
The two quantities are equal.
Quantity B is greater.
Quantity B is greater.
Suppose ABCD has sides a and b.
The length of one of ABCD's diagonals is given by a2+ b2 = c2, where c is one of the diagonals.
Note that both diagonals are of the same length.
Quantity A: The length of diagonal AC times the length of diagonal BD
This is c * c = c2.
Quantity A = c2 = a2+ b2
Now for Quantity B, remember that the perimeter of a rectangle with sides a and b is Perimeter = 2(a + b).
Half of Perimeter = (a + b)
Square Half of Perimeter = (a + b)2
Use FOIL: (a + b)2 = a2+ 2ab + b2
Quantity B = (a + b)2 = a2+ 2ab + b2
The question is asking us to compare a2+ b2 with a2+ 2ab + b2.
Note that as long as a and b are positive numbers (in this case a and b are dimensions of a rectangle, so they must be positive), the second quantity will be greater.
Example Question #152 : Geometry
If rectangle has a perimeter of , and the longer edge is times longer than the shorter edge, then how long is the diagonal ?
Lets call our longer side L and our shorter side W.
If the perimeter is equal to 68, then
.
We also have that
.
If we then plug this into our equation for perimeter, we get .
Therefore, and . Using the Pythagorean Theorem, we have so .