In a certain locality X on a river bank, every person

Question

In a certain locality X on a river bank, every person who has a dog at home also has a cat as a pet. Further, it is known that most of those who have cat as a pet do keep alligator as a pet. It has also been seen that most of those who keep cat have guests for at least 15 days in a month.

Statement: It can be said that ____1___ have guests  for ___2___ .

Select for 1 and for 2 the options that creates the most logical statement based on the information above. Make only two selections, one in each column.

chetan2u · Accepted Answer

I will add a Venn Diagram too.

1) Every person who has a dog at home also has a cat as a pet. => D is completely a part of C. D is a tiny part of C or almost equal to C, we cannot say.
2) Further, it is known that most of those who have cat as a pet do keep alligator as a pet. => More than 50% of the circle of C is covered by A. There could be A elsewhere too.
3) It has also been seen that most of those who keep cat have guests for at least 15 days in a month. => More than 50% of the circle of C is again covered by G. There could be G elsewhere too.

From 2 and 3 above, we get that there has to be some overlap at least between A and G. So, So, at least some of A is correct.
Now G is at least 15 days, so 'more than 15 days may be wrong'. It could be all are exactly 15 days we are not aware. However, at least 15 days is part of at least 10 days, so correct.

1: At least some of the aligator
2: at least 10 days

Hacchuu · Answer

Every person with a dog also has a cat
Most people with a Cat also have an alligator => Some people with a cat don't have an alligator
Most people with an Alligator have guests for at least 15 days => Few people with an Alligator don't have guests for more than 15 days.

My Answer: It can be said that  some of those who have a dog as a pet  have guests for  less than 15 days a month .
Why?
Given: Everyone who has a dog has a cat and most of them have an alligator out of which most houses get guests for 15 days minimum.

Which means:
Some who have a dog and a cat, don't have an alligator -> Cannot guess the number of days guests visit
Some who have a dog, cat and an alligator -> Have guests for less than 15 days or no guests at all.

This seems logical to me.

I'm not sure how we can infer the provided answer i.e. It can be said that  some of those who have a cat as a pet  have guests for  at least 10 days a month.

chetan2u   Bunuel   KarishmaB  can you help explain please?

KarishmaB · Answer

Either the question is not correct or I am missing something.
 
All who have a dog (say 10 people), have a cat (all 10 have a cat too). 
The reverse is not necessary. It doesn't mean that all who have a cat have a dog too. There could be many who have just cats.

Most who have a cat (could be 1000 people who have a cat), have an alligator (more than 500 have an alligator).
The reverse is not necessary. Many people (say 10,000) could have just an alligator too.

Most who have alligator (10,500 people have alligator), have guests for at least 15 days in a month (say 6000 have guests for at least 15 days a month)

Is it necessary that there has to be some overlap between these 6000 and the 1000 who have cats? No. 
I don't see how the answer is what is given. I can't conclude anything about people with cats.

chetan2u · Answer

KarishmaB  is spot on with her explanation. Let me modify the wordings to get an answer out of it.

AT1982 · Answer

All(Dog) = Cat

Most(Cat) = Alligator

Most (Cat) >= 15

Therefore, Some(Cat) = Not Alligator

Some Alligator= Not Cat

Choices

Some Alligator= <15 Days

Please explain atleast 10 Days logic?

Posted from my mobile device

Gemmie · Answer

- Has a dog => Has a cat
- Most those having a cat => Have an alligator
- Most of those having a cat => Have guest for at least 15 days/month

Analysis
+) >50% of those having a cat has an alligator
+) >50% of those having a cat has gúet for at least 15 days/month

==> There must be an overlap between cat-alligator and cat-guests over 15 days

==> At least some of those who have alligator as pet has guest for at least 15 days a month

bhattarbharat · Answer

chetan2u   KarishmaB  please tell me where I am going wrong.

People who have dogs have cats.
Most people with cats have alligators.
Most people with cats have guest for at least 15 days.

Now, if 0 people have cats, means most people do not have guests. Here, say 100 people can have  only  alligators as well. And since it cannot be inferred that having alligator implies having cats, we cannot infer anything about guests. So how is  At least some people with alligator as pet have guests for at least 10 days  justified?

KarishmaB · Answer

The question makes no sense if you assume 0 people have dogs and 0 people have cats. How do you jsutify saying "most of those who have cats have alligators"? If 0 people have cats, how does "most" work?
Some people must have cats.

KarishmaB · Answer

Solution to Updated Question:

All who have a dog (say 10 people), have a cat (all 10 have a cat too). 
The reverse is not necessary. It doesn't mean that all who have a cat have a dog too. There could be many who have just cats.

Most who have a cat (could be 1000 people who have a cat), have an alligator (more than 500 have an alligator).
The reverse is not necessary. Many people (say 10,000) could have just an alligator too.

Most who have cat (1000), have guests for at least 15 days in a month (more than 500 have guests for at least 15 days a month).

Out of 1000 cat owners, more than 500 have an alligator and more than 500 have guests for at least 15 days. There has to be some overlap between them since more figures are more than half.

ANSWER: Hence, At least some of those who have alligator as pet have guests for at least 10 days in a month.

We know that they have guests for at least 15 days but 'at least 10 days' includes all cases of 'at least 15 days'.

bumpbot · Answer

Automated notice from GMAT Club BumpBot: 

A member just gave Kudos to this thread, showing it’s still useful. I’ve bumped it to the top so more people can benefit. Feel free to add your own questions or solutions.

 This post was generated automatically.

1	2
		most of those who have alligator as pet
		At least some of those who have alligator as pet
		most of those who have dog as pet
		more than 15 days in a month.
		at least 10 days in a month.
		less than 15 days in a month.

In a certain locality X on a river bank, every person

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards

GMAT Two-part Analysis (TPA) Questions

In a certain locality X on a river bank, every person

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards