GRE Prep Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized
for You
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
The number of distinct factors of 10
[#permalink]
12 Aug 2018, 15:56
12 Aug 2018, 15:56
4
Expert Reply
2
Bookmarks
00:00
Question Stats:
66% (00:37) correct
33% (00:34) wrong based on 125 sessions
Hide Show timer Statistics
Quantity A |
Quantity B |
The number of distinct factors of 10 |
The number of distinct prime factors of 210 |
A)The quantity in Column A is greater.
B)The quantity in Column B is greater.
C)The two quantities are equal.
D)The relationship cannot be determined from the information given.
Retired Moderator
Joined: 10 Apr 2015
Posts: 6218
Given Kudos: 136
Re: The number of distinct factors of 10
[#permalink]
30 Jun 2020, 10:18
30 Jun 2020, 10:18
4
1
Bookmarks
shubham2312 wrote:
A doubt regarding this question
why we can't take -1 or -10 as a factor
as per the article -Technically, in the world of mathematics - the answer to this question is yes. There are negative factors and multiples of numbers. For example, -4 and -3 are factors of 12, -24 is a multiple of 3, and the factors of 4 would be -4, -2, -1, 1, 2, 4.
But what exactly does this mean in relation to the GRE and/or the GMAT?
For the GRE: This concept is mentioned in the ETS GRE Math Conventions PDF. You can find it here. The factors of an integer include both the positive and negative integers. This also applies for multiples.
Therefore, technically, if a GRE question were to ask "How many factors does 6 have?" The answer would be 8: (-6, -3, -2, -1, 1, 2, 3, 6). With that said, questions are very likely to specify "positive factors" or "positive integers" on the GRE. We haven't seen an official question before that required knowing that negative factors/multiples exist - but that doesn't mean those questions won't show up at all so you still want to be diligent about this.
we should consider them also.
P.S-why there is a restriction
never encountered this issue on GC
why we can't take -1 or -10 as a factor
as per the article -Technically, in the world of mathematics - the answer to this question is yes. There are negative factors and multiples of numbers. For example, -4 and -3 are factors of 12, -24 is a multiple of 3, and the factors of 4 would be -4, -2, -1, 1, 2, 4.
But what exactly does this mean in relation to the GRE and/or the GMAT?
For the GRE: This concept is mentioned in the ETS GRE Math Conventions PDF. You can find it here. The factors of an integer include both the positive and negative integers. This also applies for multiples.
Therefore, technically, if a GRE question were to ask "How many factors does 6 have?" The answer would be 8: (-6, -3, -2, -1, 1, 2, 3, 6). With that said, questions are very likely to specify "positive factors" or "positive integers" on the GRE. We haven't seen an official question before that required knowing that negative factors/multiples exist - but that doesn't mean those questions won't show up at all so you still want to be diligent about this.
we should consider them also.
P.S-why there is a restriction
never encountered this issue on GC
I agree with everything you've said. Here's what the test-makers write:
If this were an official GRE question, there would be some language that would restrict the factors (divisors) to POSITIVE values only.
For example: https://gre.myprepclub.com/forum/the-numbe ... 13805.html
Unfortunately, there are several reputable test prep companies that don't add any kind of restriction (even though that restriction is implied in the official answer)
This has been a pet peeve of mine for quite a while.
Rest assured, the GRE will always have some text that restricts the factors (divisors) to POSITIVE values only.
Cheers,
Brent
General Discussion
Re: The number of distinct factors of 10
[#permalink]
15 Aug 2018, 05:09
15 Aug 2018, 05:09
2
Expert Reply
Explanation
The factors of 10 are 1 & 10, and 2 & 5. Since there are four factors, Quantity A is 4.
The prime factors of 210 are 2, 3, 5, and 7:
Capture.PNG [ 63.82 KiB | Viewed 14531 times ]
Because 210 has four prime factors, Quantity B is also 4. The two quantities are equal.
The factors of 10 are 1 & 10, and 2 & 5. Since there are four factors, Quantity A is 4.
The prime factors of 210 are 2, 3, 5, and 7:
Attachment:
Capture.PNG [ 63.82 KiB | Viewed 14531 times ]
Because 210 has four prime factors, Quantity B is also 4. The two quantities are equal.
