shanice wrote:Hi all,

Please help me with the below data sufficiency question(Sources - Manhattan Gmat).

If x>1, what is the value of integer x?

(1)There are x unique factors of x.
(2)The sum of x and any prime number larger than x is odd.

Answer - A - Statement (1) is sufficient and Statement (2) is insufficient.

I'm having problem in understanding the first statement. What does it mean by "unique factors" in mathematical term?

Thank you.

Unique factors of x refer to numbers that divide x with 0 as remainder rmainder..

For example..
4 has 3 unique factors => 1,2,4
12 has 6 unique factors=> 1,2,3,4,6,12

How to find the number of Unique factors of a number--
1)expand the given number into multiples of prime factors
12 = 2*2*3
2)increment the power on each prime factor by one
3)find the product of the values

eg.. 56
56 = 2^3 * 7^1
Number of unique factors = (3+1)(1+1) = 8


In this particualr question..
Statement 1-
implies taht value of x is 2

Statement 2-
Not sufficient

Option A

Thank you, Rijul. So, can I conclude that "unique factors" are generally division of two integers with zero remainder?

Unique factors are just factors which are different from each other.

Take Away--

If N is a composite no.,so it can be expressed as

N=a^x*b^y*c^z; where a, b& c are prime factors & x,y,z are +ive integers..

Then,Number of unique factors=(x+1)*(y+1)*(z+1).

What does this sentence mean then?

Every integer larger than 1 has a unique prime factorization

Thank you, Sir. I understand it now.