Last visit was: 26 Apr 2024, 03:33 It is currently 26 Apr 2024, 03:33

Close
GMAT 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

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Close
Request Expert Reply
Confirm Cancel
SORT BY:
Kudos
Tags:
Show Tags
Hide Tags
Math Expert
Joined: 02 Sep 2009
Posts: 92929
Own Kudos [?]: 619106 [4]
Given Kudos: 81609
Send PM
Director
Director
Joined: 25 Jul 2018
Posts: 668
Own Kudos [?]: 1119 [3]
Given Kudos: 69
Send PM
CEO
CEO
Joined: 07 Mar 2019
Posts: 2554
Own Kudos [?]: 1813 [2]
Given Kudos: 763
Location: India
WE:Sales (Energy and Utilities)
Send PM
Director
Director
Joined: 30 Sep 2017
Posts: 956
Own Kudos [?]: 1256 [2]
Given Kudos: 402
GMAT 1: 720 Q49 V40
GPA: 3.8
Send PM
Re: If A, B and C are integers, is A + B + C even? [#permalink]
2
Kudos
(1) A - (B+C) is even
If both A and (B+C) are odd, then both A-(B+C) and A+(B+C) are even.
If both A and (B+C) are even, then both A-(B+C) and A+(B+C) are even.
SUFFICIENT

(2) (A - C)/B is odd
If both B and (A-C) are odd, then (A-C)/B is odd and A+B+C is even.
If both B and (A-C) are even, then (A-C)/B is odd and A+B+C is even.
SUFFICIENT

FINAL ANSWER IS (D)

Posted from my mobile device
Retired Moderator
Joined: 18 May 2019
Posts: 785
Own Kudos [?]: 1040 [1]
Given Kudos: 101
Send PM
Re: If A, B and C are integers, is A + B + C even? [#permalink]
1
Kudos
Given that A, B, and C are three positive integers.
We are to determine if A+B+C = an even number.
There two ways that this is possible. If all three numbers are even or if only one is even.

Statement 1: A - C - B is even
This is sufficient since statement 1 is only possible if one of the three integers is even or all the integers are even. And we know that A+B+C can only be even if all three numbers or if one of the integers is even. Statement 1 implies one of the three numbers is even hence sufficient.

Statement 2: (A-C)/B is odd
This is also sufficient. This because if both A and C are even, A-C is even, and to get an odd number, then B must also be even, since an even number can be an odd multiple and dividing by an appropriate even number will lead to an odd number. The converse, on the other hand, is not true. An odd number cannot be an even multiple. Secondly, When either A or C is odd, A-C will be odd, hence the only way to get (A-C)/B to be odd is for B to be odd, implying we will get one even number which is sufficient to conclude that A+B+C is even.
When both A and C are odd, then A-C is even, and as stated earlier, we can only get (A-C)/B to be odd if B is odd. So we end up with one even number and two odd numbers and A+B+B is even.

The answer is therefore D.
Tutor
Joined: 04 Aug 2010
Posts: 1315
Own Kudos [?]: 3136 [1]
Given Kudos: 9
Schools:Dartmouth College
Send PM
Re: If A, B and C are integers, is A + B + C even? [#permalink]
1
Kudos
Expert Reply
Quote:
If A, B and C are integers, is A + B + C even?

(1) A - C - B is even

(2) (A - C)/B is odd.


Statement 1:
Let A-C-B = 0, with the result that A = B+C.
If A=B+C=odd, then A + (B+C) = ODD + ODD = EVEN.
If A=B+C=even, then A + (B+C) = EVEN + EVEN = EVEN.
In each case, the answer to the question stem is YES.
SUFFICIENT.

Statement 2:
Let (A - C)/B = 1, with the result that A-C = B and A = B+C.
Same equation as that yielded by Statement 1.
Since Statement 1 is sufficient, Statement 2 must also be SUFFICIENT.

GMAT Club Legend
GMAT Club Legend
Joined: 18 Aug 2017
Status:You learn more from failure than from success.
Posts: 8020
Own Kudos [?]: 4098 [1]
Given Kudos: 242
Location: India
Concentration: Sustainability, Marketing
GMAT Focus 1:
545 Q79 V79 DI73
GPA: 4
WE:Marketing (Energy and Utilities)
Send PM
Re: If A, B and C are integers, is A + B + C even? [#permalink]
1
Kudos
a+b+c ; even ; e+e+e or o+o+e
#1
A - C - B is even
e-e-e or e-o-o
sufficient
#2
(A - C)/B is odd
e-e/e = Yes
(e-o)/o= yes
(o-o)/e = yes

we are getting values in e+e+e or o+o+e
sufficient
IMO D


If A, B and C are integers, is A + B + C even?

(1) A - C - B is even

(2) (A - C)/B is odd
SVP
SVP
Joined: 24 Nov 2016
Posts: 1720
Own Kudos [?]: 1344 [0]
Given Kudos: 607
Location: United States
Send PM
Re: If A, B and C are integers, is A + B + C even? [#permalink]
Quote:
If A, B and C are integers, is A + B + C even?

(1) A - C - B is even

(2) (A - C)/B is odd


odd+-even=odd
odd+-odd=even
even+-even=even

1. o+o+o=e+o=o
2. e+e+o=e+o=o
3. e+e+e=e+e=e
4. o+o+e=e+e=e

(1) A - C - B is even sufic

a-c-b=even; case 3, and 4 fit, both give an even sum.

(2) (A - C)/B is odd sufic

e/e=[odd, even, proper fraction, undefined]
o/o=[odd, proper fraction]
e/o=[even, proper fraction]
o/e=[undefined, proper fraction]

a-c/b=odd;
b=o: a-c=odd=even-odd; a,b,c=e+o+o=even.
b=e: a-c=even=even-even or odd-odd; a,b,c=e+e+e=even, and e+o+o=even.

Ans (D)

Originally posted by exc4libur on 11 Dec 2019, 05:37.
Last edited by exc4libur on 12 Dec 2019, 03:26, edited 1 time in total.
GMAT Club Bot
Re: If A, B and C are integers, is A + B + C even? [#permalink]
Moderator:
Math Expert
92929 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne