Necessary Assumption - LSAT Logical Reasoning (2024)

Class B sheets of paper cannot be recycled further.

All of the paper in Class A had been made from recycled wood pulp.

Unrecycled wood pulp is of better quality than recycled wood pulp.

When a sheet of standard printer paper is a recycled, all of its wood pulp is recovered.

The percentage of wood pulp in a sheet of standard printer paper that can be recovered during recycling varies depending on how such paper was used.

Correct answer:

When a sheet of standard printer paper is a recycled, all of its wood pulp is recovered.

Explanation:

Since 25 percent of wood pulp in the Class B sheets comes from recycled Class A sheets, the maximum number of Class B sheets is 4 times the number of Class A sheets. However, the correct answer correctly notices that the maximum number of Class B sheets can be produced only if all pulp from the Class A sheets can be recovered through recycling; if less than all of the pulp can be recovered, the actual number of Class B sheets produced will fall short of the maximum. For example, if there were 100 Class A sheets recycled, but only 25 percent of pulp could be recovered through recycling, only 100 Class B sheets could be produced.

Soccer players are faster than baseball players because soccer players use more strenuous training programs. Baseball players should use the same training programs as soccer players to become more athletic. More athletic players will be more successful.

Players who become faster become more athletic

Speed is important to success in baseball

Baseball requires different skills than soccer

Baseball players do not train very often during the season

Fast baseball players sometimes also play soccer

Correct answer:

Players who become faster become more athletic

Explanation:

The argument asserts that different training programs cause soccer players to be faster than baseball players. The next assertion is that baseball players would become more athletic if they used training programs of soccer players. This only follows if becoming faster necessarily makes one more athletic.

All car accidents result in injuries

No one who is in an accident but is uninjured deserves to be compensated

If every driver is insured, every person injured in an accident will be compensated

Those who are injured in accidents are never at fault for those accidents

Compensation always requires monetary payment

Correct answer:

If every driver is insured, every person injured in an accident will be compensated

Explanation:

If injured people might not be compensated even if every driver has insurance, then the argument's conclusion does not follow.

Students no longer prefer pencils over pens for math calculations

Production of pencil sharpeners cannot be profitable if there is a decreased demand for them

Anything that can be accomplished with pencils can also be accomplished with electronics

Availability of mechanical pencils has increased

Pencil sharpeners are only in demand for the purpose of sharpening pencils

Major coffee shops are in direct competition with internet cafes.

Public libraries are the only accessible locations where anyone can use the internet.

Internet cafes do not offer any other services, aside from online access, that would enable them to be profitable.

Internet cafes can still be profitable in other countries, just not the United States.

Internet cafes were profitable five years ago.

Correct answer:

Internet cafes do not offer any other services, aside from online access, that would enable them to be profitable.

Explanation:

The correct answer is:

Internet cafes do not offer any other services, aside from online access, that would enable them to be profitable.

The crux of the argument is that internet cafes are not successful because the service that they offer -- online access -- is now made available for free by other outlets. However, this argument depends on the assumption that internet cafes do NOT offer any other services that would make them profitable -- such as a community base that would attract clients, or food and beverages that consumers would be interested in buying.

Embezzlement is a serious crime.

Smith's conviction is nor revocable.

Embezzlement raises issues of integrity which can bar someone from practicing as an attorney.

Embezzlement demonstrates moral turpitude.

Behavior that demonstrates moral turpitude includes the commission of certain crimes.

Correct answer:

Embezzlement demonstrates moral turpitude.

Explanation:

To answer this question, it is necessary to realize that the criteria to practice law requires that a person not demonstrate moral turpitude. Therefore, there has to be a link between Smith's embezzlement and the moral turpitude. Therefore, ifembezzlement demonstrates moral turpitude, then the argument flows logically.

Some sports fans do not appreciate how short stature can be advantageous in football and basketball and how quickness can override any handicap arising from preferring the right over the left when moving on a court or field.

Evaluation of basketball players must take into account what position they play on a team, and in particular, what kind of role a coach assigns to them to effectuate the goals of the team.

Height and left-right preferences have comparable value in football and basketball.

Miles’s virtues as a basketball player should be determined by relevant statistics, such as shooting percentage and steals.

It is unfair to jump to conclusions about athletic prowess and effectiveness simply because a player is short.

Correct answer:

Height and left-right preferences have comparable value in football and basketball.

Explanation:

In any assumption question, we must identify what term, concept, or idea is expressed in the evidence that does not appear in the conclusion. In this instance, the evidence concerns football running backs. Therefore, any viable answer choice must refer meaningfully to football. Any answer choice that does not do this should be eliminated. The essence of the argument here involves an assumption that football and basketball are comparable sports. So the correct answer is: Height and left-right preferences have a comparable value in football and basketball.

Any sentient being that can experience suffering must necessarily have highly developed cognitive abilities.

Only sentient beings that can experience suffering ought to be considered outside the realm of edible food for humans.

Only organisms that are self-aware can experience suffering.

If lobsters ought not to be eaten because they can experience suffering, then the same is true with respect to pigs.

Any sentient beings that can experience suffering deserve to be treated respectfully.

Correct answer:

Only sentient beings that can experience suffering ought to be considered outside the realm of edible food for humans.

Explanation:

The assumption must speak to the issue of “experiencing suffering,” since that is the missing term in the conclusion. The correct answer links that new term to the conclusion regarding what humans ought to eat and not eat. Thus, the correct answer is: Only sentient beings that can experience suffering ought to be considered outside the realm of edible food for humans.

Writing is never improved through outlining or other time-saving strategies.

Fiction writing is a painstaking process that cannot be made easier through outlining.

The more creative the storytelling, the better the finished product, at least when it comes to fiction.

Creative narration of events in a story enhances the quality of fiction writing.

Free-writing is best used in fiction writing, but its value in expository writing is suspect.

Correct answer:

Creative narration of events in a story enhances the quality of fiction writing.

Explanation:

The conclusion speaks of free-writing as better than outlining when it comes to generating quality fiction. The premise (i.e., the evidence) for that conclusion speaks of "creative narration of events." That idea does not appear in the conclusion, so in order to link the premise to the conclusion, the assumption must address it in some meaningful way. The correct answer here does just that, by linking the idea of "creative narration of events" and the point in the conclusion about quality fiction.

The company's hiring policy has been in place long enough to determine its long-term effects.

Some new hires at the company have previously included persons who have a post-graduate degree, but no significant work experience.

Some persons with post-graduate degrees have been unable to gain significant work experience while completing their studies.

New hires are evaluated by the company every six months to determine their employee performance.

All performance evaluations by the company are done fairly and accurately.

Correct answer:

Some new hires at the company have previously included persons who have a post-graduate degree, but no significant work experience.

Explanation:

The correct answer is an unstated premise necessary to the argument’s conclusion, which is that “overall employee performance among new hires should increase.” Without this premise, it is possible that new hires’ performance will merely remain the same, as the company’s new hires may have all had significant work experience (despite it being a preference and not a requirement).

Tired of practice problems?

Try live online LSAT prep today.