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Example Questions
Example Question #2247 : Gmat Quantitative Reasoning
Note: Figure NOT drawn to scale.
Refer to the above figure. Evaluate .
Statement 1: and are complementary.
Statement 2:
EITHER statement ALONE is sufficient to answer the question.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
BOTH statements TOGETHER are insufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
Assume Statement 1 alone. and are vertical from and , respectively, so and . and form a complementary pair, so, by definition
and by substitution,
.
Assume Statement 2 alone. Since is a right triangle whose hypotenuse is times as long as a leg, it follows that is a 45-45-90 triangle, so .
, , , and together form a straight angle, so their degree measures total .
But without further information, the sum of the degree measures of only and cannot be calculated.
Example Question #22 : Lines
Note: Figure NOT drawn to scale.
Refer to the above diagram. What is the measure of ?
Statement 1: is a angle.
Statement 2:
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
BOTH statements TOGETHER are insufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
Statement 1 alone gives insufficient information to find the measure of .
, , and together form a angle; therefore,
, so by substitution,
But with no further information, the measure of cannot be calculated.
Statement 2 alone gives insufficient information for a similar reason. , , and together form a angle; therefore,
Since , we can rewrite this statement as
Again, with no further information, the measure of cannot be calculated.
Assume both statements to be true. and are a pair of vertical angles, so , and . Since , then . Also,
By substitution,
Example Question #23 : Lines
Note: You may assume that and are not parallel lines, but you may not assume that and are parallel lines unless it is specifically stated.
Refer to the above diagram. Is the sum of the measures of and less than, equal to, or greater than ?
Statement 1: There exists a point such that lies on and lies on .
Statement 2: Quadrilateral is not a trapezoid.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
BOTH statements TOGETHER are insufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
Assume Statement 1 alone. Since exists and includes , and are one and the same—and this is . Similarly, is . This means that and have a point of intersection, which is . Since falls between and and falls between and , the lines intersect on the side of that includes points and . By Euclid's Fifth Postulate, the sum of the measures of and is less than .
Assume Statement 2 alone. Since it is given that , the other two sides, and are parallel if and only if Quadrilateral is a trapezoid, which it is not. Therefore, and are not parallel, and the sum of the degree measures of same-side interior angles and is not equal to . However, without further information, it is impossible to determine whether the sum of the measures is less than or greater than .
Example Question #135 : Data Sufficiency Questions
Note: Figure NOT drawn to scale.
Refer to the above figure. Evaluate .
Statement 1:
Statement 2:
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
BOTH statements TOGETHER are insufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
Assume Statement 1 alone. and are congruent legs of right triangle , so their acute angles, one of which is , measure . and form a pair of vertical, and consequently, congruent, angles, so .
Statement 2 alone gives insufficient information, as and has no particular relationship that would lead to an arithmetic relationship between their angle measures.
Example Question #25 : Lines
Note: Figure NOT drawn to scale.
Refer to the above diagram. What is the measure of ?
Statement 1: is an equilateral triangle.
Statement 2:
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
BOTH statements TOGETHER are insufficient to answer the question.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
, , and together form a straight angle, so their measures total ; therefore,
Assume Statement 1 alone. The angles of an equilateral triangle all measure , so ; and form a pair of vertical angles, so they are congruent, and consequently, . Therefore,
But with no further information, cannot be calculated.
Assume Statement 2 alone. It follows that
Again, with no further information, cannot be calculated.
Assume both statements to be true. as a result of Statement 1, and from Statement 2, so
Example Question #141 : Data Sufficiency Questions
Note: Figure NOT drawn to scale.
Refer to the above figure. Evaluate .
Statement 1:
Statement 2:
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
BOTH statements TOGETHER are insufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
Assume Statement 1 alone. , , , and together form a straight angle, so their degree measures total .
Without further information, no other angle measures, including that of , can be found.
Assume Statement 2 alone. , , , and together form a straight angle, so their degree measures total .
Without further information, no other angle measures, including that of , can be found.
However, if both statements are assumed to be true, it follows from Statements 2 and 1 respectively, as seen before, that and , so
.
Example Question #27 : Lines
Note: Figure NOT drawn to scale.
Refer to the above figure. Give the measure of .
Statement 1:
Statement 2:
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
BOTH statements TOGETHER are insufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
BOTH statements TOGETHER are insufficient to answer the question.
Assume both statements to be true. We show that the two statements provide insufficient information by exploring two scenarios:
Case 1:
and are vertical from and , respectively, so and , and
Case 2:
The conditions of both statements are met, but assumes a different value in each scenario.
Example Question #28 : Lines
Note: Figure NOT drawn to scale.
Refer to the above diagram. Evaluate .
Statement 1:
Statement 2:
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
BOTH statements TOGETHER are insufficient to answer the question.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
Assume Statement 1 alone. , , and together form a straight angle, so their measures total ; therefore,
However, without any further information, we cannot determine the sum of the measures of and .
Assume Statement 2 alone. , , and together form a straight angle, so their measures total ; therefore,
Again, without any further information, we cannot determine the sum of the measures of and .
Assume both statements are true. Since the measures of and can be calculated from Statements 1 and 2, respectively. We can add them:
Example Question #29 : Lines
Note: Figure NOT drawn to scale.
Refer to the above diagram. Evaluate .
Statement 1:
Statement 2: is an equilateral triangle.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
BOTH statements TOGETHER are insufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
Assume Statement 1 alone. and are a pair of vertical angles, as are and . Therefore,
By substitution,
.
Assume Statement 2 alone. The angles of an equilateral triangle all measure , so .
, , and together form a straight angle, so ,
Example Question #1 : Dsq: Understanding Intersecting Lines
Refer to the above figure. Jane chose one of the line segments shown in the above diagram but she will not reveal which one. Which one did she choose?
Statement 1: One of the endpoints of the line segment is .
Statement 2: The line segment includes .
Statement 1 ALONE is sufficient to answer the question, but Statement 2 ALONE is NOT sufficient to answer the question.
BOTH statements TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient to answer the question.
BOTH statements TOGETHER are insufficient to answer the question.
EITHER statement ALONE is sufficient to answer the question.
Statement 2 ALONE is sufficient to answer the question, but Statement 1 ALONE is NOT sufficient to answer the question.
BOTH statements TOGETHER are insufficient to answer the question.
If we know both statements, then we know that the segment can be either or , since each has endpoint and each includes ; we can not eliminate either, however.