Gmat prep1 ds3
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IMO B.
What is the value of A.
a^n is multiple of 8!.
the 1st statment says that a^n = 64.it could be 2^6 or 4^3.
Insufficient.
the 2nd statment says that n = 6 i.e a^6 is multiple of 8!.
sufficient.
Its a C trap question so be careful.
What is the value of A.
a^n is multiple of 8!.
the 1st statment says that a^n = 64.it could be 2^6 or 4^3.
Insufficient.
the 2nd statment says that n = 6 i.e a^6 is multiple of 8!.
sufficient.
Its a C trap question so be careful.
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Prime factors were just a way to get to the lowest levels of factors..u r right that alone getting into terms of prime integers doesnt suffice..
But if you see 8! , you only 2 is having power >=6 .. any combination of factor which you can thus derive is not even close to 6 in its power..
Either you take 6 , 64 , 8 , , whatever
Answer would have been E if there would there would any possibility of getting any factor whose pwoer coluld have been of the form >=6
But if you see 8! , you only 2 is having power >=6 .. any combination of factor which you can thus derive is not even close to 6 in its power..
Either you take 6 , 64 , 8 , , whatever
Answer would have been E if there would there would any possibility of getting any factor whose pwoer coluld have been of the form >=6
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OA IS Brohan_vus wrote:Prime factors were just a way to get to the lowest levels of factors..u r right that alone getting into terms of prime integers doesnt suffice..
But if you see 8! , you only 2 is having power >=6 .. any combination of factor which you can thus derive is not even close to 6 in its power..
Either you take 6 , 64 , 8 , , whatever
Answer would have been E if there would there would any possibility of getting any factor whose pwoer coluld have been of the form >=6
However I have the same doubt as obgeni and not cleared, could u try again...
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I agree with rohan over here.Prime factors were just a way to get to the lowest levels of factors..u r right that alone getting into terms of prime integers doesnt suffice..
But if you see 8! , you only 2 is having power >=6 .. any combination of factor which you can thus derive is not even close to 6 in its power..
Either you take 6 , 64 , 8 , , whatever
Answer would have been E if there would there would any possibility of getting any factor whose pwoer coluld have been of the form >=6
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Ok.. let me put it this way..
When u get any number in terms of prime factors.. you are at the rootest levels of factors , which in other words is nothing but lowest levels of factors.. I guess atleast you will agree with me on this theory
Later , any other non prime factor which you get is derived by multiplying prime factors itslef.. for e.g .. 20 = is written as 2^2*5.. how many different factors it can have.. it can have 2 , 4 , 5 , 10 ... 4 u get by 2^2 ..and 10 u get by 2 *5 ...
Now our focus was the powers of the factors..Any non prime factor when its bulit ( like 10 and 4) from prime factors will always have least of the powers among the powers of individual prime factors of which its made of .
I dont know i make sense here
When u get any number in terms of prime factors.. you are at the rootest levels of factors , which in other words is nothing but lowest levels of factors.. I guess atleast you will agree with me on this theory
Later , any other non prime factor which you get is derived by multiplying prime factors itslef.. for e.g .. 20 = is written as 2^2*5.. how many different factors it can have.. it can have 2 , 4 , 5 , 10 ... 4 u get by 2^2 ..and 10 u get by 2 *5 ...
Now our focus was the powers of the factors..Any non prime factor when its bulit ( like 10 and 4) from prime factors will always have least of the powers among the powers of individual prime factors of which its made of .
I dont know i make sense here