Not able to understand :(

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by kmittal82 » Wed Sep 07, 2011 6:18 am
But 90 (assuming n = 30 as given by the answer) isn't a factor of 1815
Infact, none of the numbers mentioned in the list, when multiplied by 3, are factors of 1815.

... unless I have grossly misundertsood the question :)

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by Brent@GMATPrepNow » Wed Sep 07, 2011 7:02 am
Ashetty wrote:What is the greatest value of a positive integer n such that 3n is a factor of 1815?

15
18
30
33
45

Ans : C
1815 is the greatest possible factor of 1815
Since (3)(605)=1815, we can see that if n=605 then 3n will be a factor of 1815

So, the answer must be [spoiler]605 (which does not appear as an answer choice)[/spoiler]

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by Ashetty » Wed Sep 07, 2011 7:06 am
Question number 20.So we shouldn't believe this website than?..
https://www.bestsamplequestions.com/gmat ... ons-1.html

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by Brent@GMATPrepNow » Wed Sep 07, 2011 7:17 am
Ashetty wrote:Question number 20.So we shouldn't believe this website than?..
https://www.bestsamplequestions.com/gmat ... ons-1.html

Thanks!
Since I haven't looked into all of its questions, I wouldn't go as far as denouncing the entire website :-), but I can tell you that question #20 has some problems.

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by navami » Thu Sep 08, 2011 4:49 am
Yes 605 is the rite answer here considering 1815 is the largest factor of 1815.
if we have to find the value of N and largest factor is not equal to 1815 then the ans will be 121.
This time no looking back!!!
Navami