x a prime

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x a prime

by sanju09 » Sun Apr 11, 2010 11:55 pm
Is x a prime number?

(1) x is an even number.

(2) x can not be divided evenly by an odd number other than 1.
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Source: — Data Sufficiency |

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by thephoenix » Mon Apr 12, 2010 12:23 am
IMO B

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by ajith » Mon Apr 12, 2010 12:38 am
sanju09 wrote:Is x a prime number?

(1) x is an even number.

(2) x can not be divided evenly by an odd number other than 1.
1) is not enough to conclude that x is a prime or not

2) is also not sufficient to conclude x is a prime ( 2 is a prime, 4 is not a prime)

Combining 2 statements also will not yield anything new

E, IMO
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by gmatmachoman » Mon Apr 12, 2010 12:46 am
ajith wrote:
sanju09 wrote:Is x a prime number?

(1) x is an even number.

(2) x can not be divided evenly by an odd number other than 1.
1) is not enough to conclude that x is a prime or not

2) is also not sufficient to conclude x is a prime ( 2 is a prime, 4 is not a prime)

Combining 2 statements also will not yield anything new

E, IMO
+1 for E

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by kstv » Mon Apr 12, 2010 1:49 am
Is x a prime number?
(1) x is an even number.
(2) x can not be divided evenly by an odd number other than 1.

(2) x cannot be divided by any odd numbers,
no factor of x is an odd number , or
every factor of x is even number
possible only if x = 2,2²..........
Insuff
(1) says nothing new. Insuff

only if x = 2 then it is a prime.

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by sanju09 » Mon Apr 12, 2010 2:22 am
If u can answer the 4 questions you are already a Manager, chuck GMAT.
How do you put a giraffe into a refrigerator?
How do you put an elephant into a refrigerator?
The Lion King is hosting an animal conference, all the animals attend except one. Which animal does not attend?
There is a river you must cross, but it is inhabited by crocodiles, and there is no bridge. How do you manage it?
Task 1

How do you put a giraffe into a refrigerator?

Solution

This can be done in following 3 steps:

1. Open the refrigerator door.

2. Throw the giraffe in.

3. Shut the refrigerator door.

Task 2

How do you put an elephant into a refrigerator?

Solution

This can be done in following 4 steps:

1. Open the refrigerator door.

2. Take the giraffe out.

3. Throw the elephant in.

4. Shut the refrigerator door.

Task 3

The Lion King is hosting an animal conference, all the animals attend except one. Which animal does not attend?

Solution

The elephant did not attend the conference, as it was dumped in the refrigerator.

Task 4

There is a river you must cross, but it is inhabited by crocodiles, and there is no bridge. How do you manage it?

Solution

I will just swim down across the river all safely, as there's no crocodile there, all are there in the Lion King's animal conference.

feel free to write to me if you still find a crocodile in the river, I'll take it to the notice of the Lion King and legal actions shall be taken against the crook.
The mind is everything. What you think you become. -Lord Buddha



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by kstv » Mon Apr 12, 2010 2:37 am
sanju09 wrote:

feel free to write to me if you still find a crocodile in the river, I'll take it to the notice of the Lion King and legal actions shall be taken against the crook.
sanju09 the Certified manager means

legal action will be taken against the croc.
minor error in drafting can be overlooked.

Got this is the flotsam of information on the Net. It seems 90% of Managers in a survey got it wrong but kids did very well.
What are the Managerial qualities, that are being evaluted by these Qs?
someone other than sanju09

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by Fiver » Mon Apr 12, 2010 6:00 am
Agree with E.
Is x prime?

st1] x is an even number.
x could be 2 or any power of 2 or a combination of 2 and odd integers.
Insuff.

st2] x can not be divided evenly by an odd number other than 1.
x could again be 2 or any power of 2 or an odd prime number.

Together x could be 2 or any power of 2.

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by ajith » Mon Apr 12, 2010 6:16 am
sanju09 wrote:
If u can answer the 4 questions you are already a Manager, chuck GMAT.
How do you put a giraffe into a refrigerator?
How do you put an elephant into a refrigerator?
The Lion King is hosting an animal conference, all the animals attend except one. Which animal does not attend?
There is a river you must cross, but it is inhabited by crocodiles, and there is no bridge. How do you manage it?

This Question is non-GMATish and conflicts with the purpose of GMAT. On second thoughts, I will move it to non-critical reasoning forum.
Always borrow money from a pessimist, he doesn't expect to be paid back.

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by Cdawg » Mon Apr 12, 2010 8:47 am
(1) x could be 2, which is prime, but also 4, which isn't prime => insufficient
(2) x could be 1;4;8;10;etc. which aren't prime, but also be 2, which is prime = > insufficient

together: if x is even AND not divisible by any other odd number than 1, x could be 2, which is prime, but also be 4, which is not prime = > insufficient
Thus answer is: E

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by sanju09 » Thu Apr 22, 2010 10:25 pm
ajith wrote:
sanju09 wrote:
If u can answer the 4 questions you are already a Manager, chuck GMAT.
How do you put a giraffe into a refrigerator?
How do you put an elephant into a refrigerator?
The Lion King is hosting an animal conference, all the animals attend except one. Which animal does not attend?
There is a river you must cross, but it is inhabited by crocodiles, and there is no bridge. How do you manage it?

This Question is non-GMATish and conflicts with the purpose of GMAT. On second thoughts, I will move it to non-critical reasoning forum.
Why quote me, when it's not posted by me, man? Didn't you hear PLAGIARISM here?
The mind is everything. What you think you become. -Lord Buddha



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