Cannot Be True Question Problem Set & Answer Key

Problem Set 
1. For a ten-month period, the total monthly sales of new cars within the country of Calistan remained constant. During this period the monthly sales of new cars manufactured by Marvel Automobile Company doubled, and its share of the new car market within Calistan increased correspondingly. At the end of this period, emission standards were imposed on new cars sold within Calistan. During the three months following this imposition, Marvel Automobile Company’s share of the Calistan market declined substantially even though its monthly sales within Calistan remained constant at the level reached in
the last month of the ten-month period.
If the statements above are true, which one of the
following CANNOT be true?
(A) The total monthly sales within Calistan of new
cars by companies other than Marvel
Automobile Company decreased over the
three months following the imposition of the
emission standards.
(B) Over the three months before the imposition of
the emission standards, the combined market
share of companies other than Marvel
Automobile Company selling new cars in
Calistan decreased.
(C) If the emission standards had not been imposed,
Marvel Automobile Company would have
lost an even larger share of the number of
new cars sold in Calistan than, in fact, it did.
(D) A decrease in the total monthly sales of new
cars within Calistan will occur if the emission
standards remain in effect.
(E) Since the imposition of the emission standards,
Marvel Automobile Company’s average
profit on each new car sold within Calistan
has increased.
2. Two things are true of all immoral actions. First, if they are performed in public, they offend public sensibilities. Second, they are accompanied by feelings of guilt.
If all the statements above are true, then which one of
the following must be false?
(A) Some immoral actions that are not performed in
public are not accompanied by feelings of
guilt.
(B) Immoral actions are wrong solely by virtue of
being accompanied by feelings of guilt.
(C) Some actions that offend public sensibilities if
they are performed in public are not
accompanied by feelings of guilt.
(D) Some actions that are accompanied by feelings
of guilt are not immoral, even if they
frequently offend public sensibilities.
(E) Every action performed in public that is
accompanied by feelings of guilt is immoral.
Answer Key
All answer keys in this book indicate the source of the question by giving the month and year the LSAT
was originally administered, the Logical Reasoning section number, and the question number within that
section. Each LSAT has two Logical Reasoning sections, and so the Section 1 and Section 2 designators
will refer to the first or second Logical Reasoning section in the test, not the physical section number of the
booklet.
Question #1. Cannot-#%. June 2000 LSAT, Section 1, #15. The correct answer choice is (A)
This question is a repeat of a question that appeared on the March 1985 LSAT (remember, on the LSAT
past is prologue). The topic of the original question was also the car market, but the company in question
was called Superb Automobile. Several of the answer choices, including the correct answer, were virtually
identical to the answers in this problem.
Let us first review the facts given in the stimulus:
Statement: For a ten-month period, the total monthly sales of new cars within the country of
Calistan remained constant.
The wording of this statement should alert you that numbers and percentages in the form of market
share (“monthly sales...remained constant”) may be an issue in this problem. Note that the
statement is a simple fact; no explanation is given for why the total sales stayed constant.
Statement: During this period the monthly sales of new cars manufactured by Marvel Automobile
Company doubled, and its share of the new car market within Calistan increased
correspondingly.
If total monthly sales of new cars remains constant and Marvel’s sales doubled, then Marvel’s share
of the new car market must also have doubled. Again, no explanation for Marvel’s increase is
given; the increase is just stated as a fact.
Statement: At the end of this period, emission standards were imposed on new cars sold within
Calistan.

Cannot Be True Question Review

In Cannot Be True questions your task is to identify the answer choice that
cannot be true or is most weakened by the information in the argument.
Answers that could be true are incorrect. The stimulus in a Cannot Be True
question rarely contains a conclusion.
For the Fourth Question Family, the following rules apply:
1. Accept the stimulus information and use only it to prove that one of the
answer choices cannot occur.
2. If an answer choice contains information that does not appear directly in
the stimulus or as a combination of items in the stimulus, then that
answer choice could be true, and it is incorrect. The correct answer
choice will directly disagree with the stimulus or a consequence of the
stimulus.
Cannot Be True questions can be worded in a variety of ways, but the gist of
the question type is to show that an answer cannot follow, and this tends to be
executed in three separate ways:
1. Stating that the answer cannot be true or does not follow.
2. Stating that the answer could be true EXCEPT.
3. Stating that the answer choice must be false.
Cannot Be True questions are tricky because the concept of an answer choice
being possibly true and therefore wrong is counterintuitive. When you
encounter a Cannot Be True question, you must mentally prepare yourself to
eliminate answers that could be true or are possible, and select the one answer
choice that cannot be true or is impossible.
In problems that revolve around numbers and percentages, the stimulus will
often supply enough information for you to determine that certain outcomes
must occur. The correct answer then violates this outcome.
In problems featuring conditional statements, many different scenarios can
occur, except the following:
The sufficient condition occurs, and the necessary condition does not
occur.
Thus, when a conditional statement is made in a Cannot Be True question
stimulus, you should actively seek the answer that matches the scenario above.