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.
Sep 28Live Online Class with Top GRE Expert Mike Butville
08:00 PM EDT
-10:00 PM EDT
Top scores are possible when you enroll in a powerful GRE course, taught live online + 6 months access to TTP GRE OnDemand video courses included! Class starts Mon/Wed Sept. 28, 2026 - Dec. 9, 2026, 8:00pm-10:00pm EST
If a is a positive integer, then which of the following must
[#permalink]
06 Aug 2017, 12:37
06 Aug 2017, 12:37
1
Expert Reply
4
Bookmarks
00:00
Question Stats:
54% (01:08) correct
45% (01:10) wrong based on 209 sessions
Hide Show timer Statistics
If a is a positive integer, then which of the following must be true of (a − 1)(a)(a + 1)?
Indicate all that apply.
❑ It is always positive.
❑ It is always odd.
❑ It is always divisible by 3.
❑ It is always divisible by 4.
❑ It is non-prime.
Re: If a is a positive integer, then which of the following must
[#permalink]
24 Sep 2017, 07:31
24 Sep 2017, 07:31
2
Let's check the answers one by one
❑ It is always positive: if n = 1, then we have 0*1*2 = 0 and 0 is neither positive nor negative
❑ It is always odd: if n = 2, then we have 1*2*3 = 6 and 6 is even
❑ It is always divisible by 3: if we start with n = 1, we get 0 that is divisible for every number, then if n=1, we get 6, if n=2, we get 24, if n=3, we get 60 and so on
❑ It is always divisible by 4: if n = 2, then we have 6 as before and 6 is not divisible by 4
❑ It is non-prime: same argument as for "divisible by 3", the result is never prime.
Thus the answers are C and E
❑ It is always positive: if n = 1, then we have 0*1*2 = 0 and 0 is neither positive nor negative
❑ It is always odd: if n = 2, then we have 1*2*3 = 6 and 6 is even
❑ It is always divisible by 3: if we start with n = 1, we get 0 that is divisible for every number, then if n=1, we get 6, if n=2, we get 24, if n=3, we get 60 and so on
❑ It is always divisible by 4: if n = 2, then we have 6 as before and 6 is not divisible by 4
❑ It is non-prime: same argument as for "divisible by 3", the result is never prime.
Thus the answers are C and E
Re: If a is a positive integer, then which of the following must
[#permalink]
26 Jul 2021, 10:55
26 Jul 2021, 10:55
1
It's important to note that we know it is divisible by 3 because (a-1)(a)(a+1) represents three consecutive integers. Since the question states it is a positive integer, we know that it will always result in a multiple of 3.
