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Example Questions
Example Question #781 : Data Sufficiency Questions
Consider segment with midpoint at the point .
I) Point has coordinates of .
II) Segment has a length of units.
What are the coordinates of point ?
Statement II is sufficient to answer the question, but statement I is not sufficient to answer the question.
Statement I is sufficient to answer the question, but statement II is not sufficient to answer the question.
Either statement alone is sufficient to answer the question.
Both statements are necessary to answer the question.
Neither I nor II are sufficient to answer the question. More information is needed.
Statement I is sufficient to answer the question, but statement II is not sufficient to answer the question.
In this case, we are given the midpoint of a line and asked to find one endpoint.
Statement I gives us the other endpoint. We can use this with midpoint formula (see below) to find our other point.
Midpoint formula:
Statment II gives us the length of the line. However, we know nothing about its orientation or slope. Without some clue as to the steepness of the line, we cannot find the coordinates of its endpoints. You might think we can pull of something with distance formula, but there are going to be two unknowns and one equation, so we are out of luck.
So,
Statement I is sufficient to answer the question, but statement II is not sufficient to answer the question.
Example Question #782 : Data Sufficiency Questions
Find endpoint given the following:
I) Segment has its midpoint at .
II) Point is located on the -axis, points from the origin.
Either statement is sufficient to answer the question.
Statement II is sufficient to answer the question, but statement I is not sufficient to answer the question.
Statement I is sufficient to answer the question, but statement II is not sufficient to answer the question.
Both statements are needed to answer the question.
Neither statement is sufficient to answer the question. More information is needed.
Both statements are needed to answer the question.
Find endpoint Y given the following:
I) Segment RY has its midpoint at (45,65)
II) Point R is located on the x-axis, 13 points from the origin.
I) Gives us the location of the midpoint of our segment
(45,65)
II) Gives us the location of one endpoint
(13,0)
Use I) and II) to work backwards with midpoint formula to find the other endpoint.
So endpoint is at .
Therefore, both statements are needed to answer the question.
Example Question #791 : Data Sufficiency Questions
Consider segment
I) Endpoint is located at the origin
II) has a distance of 36 units
Where is endpoint located?
Both statements are needed to answer the question.
Neither statement is sufficient to answer the question. More information is needed.
Either statement is sufficient to answer the question.
Statement I is sufficient to answer the question, but Statement II is not sufficient to answer the question.
Statement II is sufficient to answer the question, but Statement I is not sufficient to answer the question.
Neither statement is sufficient to answer the question. More information is needed.
To find the endpoint of a segment, we can generally use the midpoint formula; however, in this case we do not have enough information.
I) Gives us one endpoint
II) Gives us the length of DF
The problem is that we don't know the orientation of DF. It could go in infinitely many directions, so we can't find the location of without more information.
Example Question #791 : Data Sufficiency Questions
is the midpoint of line PQ. What are the coordinates of point P?
(1) Point Q is the origin.
(2) Line PQ is 8 units long.
Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
Statements (1) and (2) TOGETHER are NOT sufficient.
Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
EACH statement ALONE is sufficient.
Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
The midpoint formula is
,
with statement 1, we know that Q is and can solve for P:
and
Statement 1 alone is sufficient.
Statement 2 doesn't provide enough information to solve for point P.