GMAT Prep Test 1 Q33

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Source: — Data Sufficiency |

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by akshatsingh » Sun May 11, 2008 10:46 pm
1) The sum of two digits of n is prime

n=83
n=29

Not Sufficent

2) Each of the two digts is prime.
8 and 9 are not prime. So n cannot be greater than 80.

Sufficent.


My answer is B.
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by sandeep_chhabra » Mon May 12, 2008 12:08 am
Got it now.....
Thanks

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by II » Mon May 12, 2008 12:23 pm
akshatsingh wrote:
2) Each of the two digts is prime.
8 and 9 are not prime. So n cannot be greater than 80.

Sufficent.

My answer is B.
Another way of looking at this:
We know that the following are the single-digit prime numbers: 2, 3, 5, and 7.
So if each of the 2 digits is prime, then the maximum value we can have is 77. This is less than 80 ... so n < 80. SUFFICIENT. Answer B.

What is the Official answer ?

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by Alejandro » Mon May 19, 2008 6:41 pm
ok , but consider this, the first statement says that the sum of the 2 digits also is prime number, if you take in count this 2+3=5 so the number could be 23 that is less than 80, maybe the answer could be c, what do you think?

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by akshatsingh » Tue May 20, 2008 2:14 am
Experts say that if either of A or B is sufficent .. D can be a possibilty but not C.

best advise would be to read the instructions little more carefully.. jsut once :)
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