If x and y are greater than 1, is the largest prime factor of x greate

Question

If x and y are greater than 1, is the largest prime factor of x greater than the largest prime factor of y?

(1) x = 7^n
(2) The least common multiple of x and y is 105.

raarun · Answer

Statement 1 > Does not say anything about y so it is not sufficient
Statement 2 > LCM=105. 
Sample 1 :
The question does not state that x has to be a integer x can be 15  \sqrt{7}  and y can be 
105 in this case the the largest prime factor of x (5)is less than the largest prime factor of Y (7)
or
Sample 2:
x=7 and y=105 in which case the large prime factors are the same

Combining 1 and 2 is still not sufficient as inferred from sample 1 above

Ans E

ic16 · Answer

Also had trouble with this one - my answer was E.

(1) x highest prime factor is 7
(2) taking all prime factors of X and Y will result in 3x5x7 (without any powers)
(1)(2) Already know that x's highest prime factor is 7 and together they form 3x5x7, so y's prime factors will include necessarily 3 and 5. What we have to know is whether y includes 7 or not. No element was provided to answer this question, so E

bumpbot · Answer

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If x and y are greater than 1, is the largest prime factor of x greate

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