It is difficult to grow cacti in a humid climate. It is difficult to r

Question

It is difficult to grow cacti in a humid climate. It is difficult to raise orange trees in a cold climate. In most parts of a certain country, it is either easy to grow cacti or easy to raise orange trees.

If the statements above are true, which one of the following must be false?

(A) Half of the country is both humid and cold.
(B) Most of the country is hot.
(C) Some parts of the country are neither cold nor humid.
(D) It is not possible to raise cacti in the country.
(E) Most parts of the country are humid.

generis · Accepted Answer

Skywalker18 - hilarious. To answer this question, we do not have to decide whether either/or includes both (it does). On other questions, though, we do have to decide whether either/or includes both. On the LSAT, in your statement, you are saying that you would be content to drink 1) bourbon, 2) scotch, or (3) both bourbon and scotch (not necessarily at the same time, although be my guest and take aspirin before you sleep . . . .

) Your either does rule out all other potables. At the same time, on the LSAT, a mere either/or tells the bartender that both bourbon and scotch will satisfy you; he can choose one, the other, or both. You may drink only bourbon. You may drink only scotch. But you may also, according to the LSAT, drink both bourbon and scotch. Maybe you alternate them. But maybe you mix them. (No. You wouldn't.

But LSAT logic says that you can drink both simultaneously.) On the LSAT, unless another pre-existing "trigger" condition exists, or unless the text says, "BUT NOT BOTH," an either/or statement means Either X or Y • Either X or Y - What is possible? X can happen, and not Y. Y can happen, and not X. Both X and Y can happen. What is not possible? Neither X nor Y happens. At least one of those things must happen, AND both can happen. But at least one must happen. The "at least one" rule is what I would use here. Again, we do not need to worry about whether the either/or statement is inclusive (it is). This logic is tough to explain; it's easier to use numbers. In words—the word "most" rescues us from having to decide whether either/or includes both. Premises • It is difficult to grow cacti in a humid climate. If cacti grow, the climate is not humid. • It is difficult to raise orange trees in a cold climate. If orange trees grow, the climate is not cold. We have no initial conditions (prior to these) that restrict us. -- "not humid" and "not cold" are not mutually exclusive. -- LSAT inclusiveness: the statement implies that in most parts, growing both is possible -- LSAT, make it easier: use at least one . Growing at least one of them is possible in the more than half of the country • Final premise - we have to satisfy the last statement. In most parts of a certain country, it is either easy to grow cacti or easy to raise orange trees. We can satisfy that statement using an exclusionary OR. We can satisfy that statement using an and inclusive OR. Exclusionary OR Let's say that -- 49% of the country is not humid, but IS cold. Only cacti grow there. -- 1% of the country is not cold, but IS humid. Only orange trees grow there. That setup will not work. We have covered 50%, which is not "most." We have not satisfied the last premise. Change the percentages. -- 50% of the country is not humid, but IS cold. Only cacti grow there. -- 1% of the country is not cold, but IS humid. Only orange trees grow there. That works. Now 51% of the country has the proper things growing, and 51% of the country therefore either is not humid or is not cold. In 51% of the country, at least one of these is true: it is not humid or it is not cold. 51% of the country, as in A, cannot be both humid and cold. If 51% of the country is both humid and cold, then at least one cannot grow in most parts of the country. Statement A is false. Both humid and cold contradicts the "at least one" exclusionary approach. Both humid and cold means "neither dry nor warm,"* and neither/none is the opposite of at least one, just as in Quant. *I'm using these adjectives for this option only because double negatives are hard. The more accurate phrasing is that in Option A "Both humid and cold in most" means "NEITHER not humid nor not cold in most." Inclusive OR Easier - if the LSAT does not say "but not both," then either/or means "possibly both." Possibly both cacti and orange tree means possibly both not humid and not cold Most of the country is either not humid or not cold or IS both not humid and not cold. Statement A says: Most of the country IS both humid and cold. Flat contradiction. Option A must be false. Hope that helps. I buy you a virtual bourbon or scotch -- or both.

ImHSB88 · Answer

I think the answer is A.

Cacti and Orange cant be grown simultaneously.

"it is either easy to grow cacti  or  easy to raise orange trees."

Skywalker18 · Answer

It is difficult to grow cacti in a humid climate. It is difficult to raise orange trees in a cold climate. In most parts of a certain country, it is either easy to grow cacti or easy to raise orange trees.

Type- Must be false
Boil it down- In most parts of a certain country, it is either easy to grow cacti or easy to raise orange trees. 
-- In most of the country, it is either not humid or not cold

(A) Half of the country is both humid and cold.- Correct; contradicts the final sentence, that says "in more than 50 percent or more of the country, it's easy to grow at least one of cacti/oranges."
(B) Most of the country is hot. - incorrect; Maybe 
(C) Some parts of the country are neither cold nor humid. - incorrect; 'Some' could be a small percentage and thus easily can be true
(D) It is not possible to raise cacti in the country.- incorrect;
(E) Most parts of the country are humid. - incorrect; may be true;

Answer A

Question- In most parts of a certain country, it is either easy to grow cacti or easy to raise orange trees. --> Does it mean that in most parts, it is easy to grow either cacti or orange  but not both ?

I would like to drink bourbon or scotch-- I think it means either of them but not both.

AjiteshArun  ,  GMATNinja  ,  MagooshExpert  ,  GMATGuruNY  ,  VeritasPrepBrian  ,  MartyMurray  ,  DmitryFarber  ,  daagh  ,  generis  , other experts - please enlighten

manishcmu · Answer

In my opinion, the set logic is still valid here i.e either-or statement can include both. This is how I interpreted the last sentence -
In most parts of a certain country, it is either easy to grow cacti or easy to raise orange trees => In most parts of a certain country, it is either not humid (~H) or not cold (~C) (assume 70%). This 70% can include both not humid (~H) and not cold (~C), but can never include both humid (H) and cold (C). So, definitely both humid and cold must be 30% or less.

Gladiator59 · Answer

Official Explanation -

Where formal logic is concerned, even one word can make a big difference.

The operative word in the stimulus is “most.” If in most parts—that is, in “well beyond 50%”—of this country, it’s either easy to grow cacti (meaning that those parts are not humid) or easy to raise orange trees (meaning that those parts are not cold), then most of the country has to be either not humid, or not cold, or both. For that reason (A) has to be false. If (A) were true—if half of the country were indeed both humid and cold—then at maximum, only the other 50% of the country could grow cacti or raise oranges with the ease that the stimulus describes. And 50% doesn’t qualify as “most.”
Meanwhile, three of the wrong choices could be true, and one of them must be:

(B) The terms of the argument are “humid” and “cold.” “Hot” is never mentioned, so it’s eminently possible for the entire country (let alone most of it) to be hot.

(C) Has to be true. In fact, the “some parts” of which (C) speaks have to comprise the majority—the parts where it’s easy to grow cacti or raise oranges or both.

(D) This statement could be true. The stimulus only requires that it is easy to grow cacti or orange trees in most parts of the country. It could be impossible to grow cacti in the country as long as it is easy to grow orange trees in most parts of the country.

(E) Could be true. If true, then most of the country must not be cold so as to make it easy to raise orange trees there. That’s consistent with the stimulus.

Always a delight to solve such tricky formal logic questions.

Very easy to get wrong when in a hurry.

As usual generis hits the nail on its head and then some. +1 for that.

Very easy to get wrong when in a hurry. As usual generis hits the nail on its head and then some. +1 for that.

berdibekov · Answer

please help me with option D "It is not possible to raise cacti in the country." Why is it incorrect? The passage states that "In most parts of a certain country, it is either easy to grow cacti or easy to raise orange trees." So how impossibility of raising cacti is true?

Thanks in advance!

Thanks in advance!

Rishovnits · Answer

Hi,

So lets assume D is correct and "must be false". Hence, it implies that  "it is possible to raise cacti in the country. " Now per the conclusion, most parts of a certain country means >51% to 100% of the country can grow either cacti or orange. If anywhere from 51 to 100% of the area can grow cacti ,then bolded part is correct. But if 100% of the orange trees can be grown (can be true), then bolded part is not correct. So overall option D is incorrect.

Arro44 · Answer

I would go with AC A

We know that most of the country allows for at least one of the plants to be cultivated.

Therefore, at least 50.1% of the country have to bee either non-humid or non-cold.
If half of the country would be cold and humid, conditions in which neither of the plants grow, the original statement about the majority of the country to be favourable to one of the two plants would hold no longer.

Therefore, for the OS to hold AC A has to be wrong.

auradediligodo · Answer

It is difficult to grow cacti in a humid climate. It is difficult to raise orange trees in a cold climate. In most parts of a certain country, it is either easy to grow cacti or easy to raise orange trees.

If the statements above are true, which one of the following must be false?

Pre-thinking

We should first note the wording used in the question:    must be false  .

Second we should pay attention to the wording used in the argument, especially to    most parts of   and  either or

POE:

(A)   Half of the country is both humid and cold.
 We now that the either A or C situation applies to  most  of the country. Plus note that most means more than 50%. So this option cannot be true. Correct

(B) Most of the country is hot.
 That's possibility. OUT

(C) Some parts of the country are neither cold nor humid.
 The argument says that in   most parts of a country...  So in th remaining parts this scenario could occur. OUT

(D) It is not possible to raise cacti in the country.
   Either A or C   condition makes this statement valid

(E) Most parts of the country are humid.
 same reasoning used in D

GurpreetMahli · Answer

Bunuel  The poster of the question  Gladiator59  has posted an official explanation in the thread and reasoned the correct answer choice as  C . But the system has marked the correct answer as  A .

Would you be able to reconcile this?

I marked C. 
--
(A) Half of the country is both humid and cold.
(B) Most of the country is hot.
(C) Some parts of the country are neither cold nor humid.
(D) It is not possible to raise cacti in the country.
(E) Most parts of the country are humid.

Bunuel · Answer

The OE also says that the correct answer is A. Please check again.

GurpreetMahli · Answer

The official explanation has it marked and reasoned for  C . I pasted below what I referenced , OFFICIAL Explanation posted by  Gladiator59 , it is in the threads toward the bottom. 
   Official Explanation -

Where formal logic is concerned, even one word can make a big difference.

The operative word in the stimulus is “most.” If in most parts—that is, in “well beyond 50%”—of this country, it’s either easy to grow cacti (meaning that those parts are not humid) or easy to raise orange trees (meaning that those parts are not cold), then most of the country has to be either not humid, or not cold, or both. For that reason  (A) has to be false . If (A) were true—if half of the country were indeed both humid and cold—then at maximum, only the other 50% of the country could grow cacti or raise oranges with the ease that the stimulus describes. And 50% doesn’t qualify as “most.” 
Meanwhile, three of the wrong choices could be true, and one of them must be:

(B) The terms of the argument are “humid” and “cold.” “Hot” is never mentioned, so it’s eminently possible for the entire country (let alone most of it) to be hot.

(C) Has to be true. In fact, the “some parts” of which (C) speaks have to comprise the majority—the parts where it’s easy to grow cacti or raise oranges or both.

(D) This statement could be true. The stimulus only requires that it is easy to grow cacti or orange trees in most parts of the country. It could be impossible to grow cacti in the country as long as it is easy to grow orange trees in most parts of the country.

(E) Could be true. If true, then most of the country must not be cold so as to make it easy to raise orange trees there. That’s consistent with the stimulus.

Always a delight to solve such tricky formal logic questions.  https://gmatclub.com/forum/images/smilies/1f603.png  Very easy to get wrong when in a hurry.

As usual  generis  hits the nail on its head and then some. +1 for that.  https://gmatclub.com/forum/images/smilies/1f603.png

Bunuel · Answer

QUESTION:

It is difficult to grow cacti in a humid climate. It is difficult to raise orange trees in a cold climate. In most parts of a certain country, it is either easy to grow cacti or easy to raise orange trees.

If the statements above are true,    which one of the following must be   false  ?

Official Explanation -

Where formal logic is concerned, even one word can make a big difference.

The operative word in the stimulus is “most.” If in most parts—that is, in “well beyond 50%”—of this country, it’s either easy to grow cacti (meaning that those parts are not humid) or easy to raise orange trees (meaning that those parts are not cold), then most of the country has to be either not humid, or not cold, or both.    For that reason (A) has to be false.    If (A) were true—if half of the country were indeed both humid and cold—then at maximum, only the other 50% of the country could grow cacti or raise oranges with the ease that the stimulus describes. And 50% doesn’t qualify as “most.”

Meanwhile, three of  the wrong choices  could be true, and one of them must be:

(B) The terms of the argument are “humid” and “cold.” “Hot” is never mentioned, so it’s eminently possible for the entire country (let alone most of it) to be hot.

(C) Has to be true. In fact, the “some parts” of which (C) speaks have to comprise the majority—the parts where it’s easy to grow cacti or raise oranges or both.

(D) This statement could be true. The stimulus only requires that it is easy to grow cacti or orange trees in most parts of the country. It could be impossible to grow cacti in the country as long as it is easy to grow orange trees in most parts of the country.

(E) Could be true. If true, then most of the country must not be cold so as to make it easy to raise orange trees there. That’s consistent with the stimulus.

GurpreetMahli · Answer

My apologizes

, not only did I miss that I completely missed the question which one must be false. Makes a lot more sense now, lol.

It is difficult to grow cacti in a humid climate. It is difficult to r

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