Author 
Message 
TAGS:

Hide Tags

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6028
GPA: 3.82

If x, y, and z are positive integers, is x+y divisible by 5? 1) x+z is
[#permalink]
Show Tags
22 Aug 2017, 01:22
Question Stats:
64% (00:58) correct 36% (00:50) wrong based on 137 sessions
HideShow timer Statistics
If x, y, and z are positive integers, is x+y divisible by 5? 1) x+z is divisible by 5 2) y+z is divisible by 5
Official Answer and Stats are available only to registered users. Register/ Login.
_________________
MathRevolution: Finish GMAT Quant Section with 10 minutes to spare The oneandonly World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy. "Only $99 for 3 month Online Course" "Free Resources30 day online access & Diagnostic Test" "Unlimited Access to over 120 free video lessons  try it yourself"



Math Expert
Joined: 02 Sep 2009
Posts: 47983

Re: If x, y, and z are positive integers, is x+y divisible by 5? 1) x+z is
[#permalink]
Show Tags
22 Aug 2017, 01:26



Director
Joined: 18 Aug 2016
Posts: 631
Concentration: Strategy, Technology
GMAT 1: 630 Q47 V29 GMAT 2: 740 Q51 V38

Re: If x, y, and z are positive integers, is x+y divisible by 5? 1) x+z is
[#permalink]
Show Tags
23 Aug 2017, 03:32
MathRevolution wrote: If x, y, and z are positive integers, is x+y divisible by 5?
1) x+z is divisible by 5 2) y+z is divisible by 5 (1) tells us x,z can take (0,5),(5,0).... also no information about y..not sufficient (2) tells us y,z can take (0,5),(5,0).... also no information about x..not sufficient on combining x,y can take (0,0) or (5,5) ...not sufficient E
_________________
We must try to achieve the best within us
Thanks Luckisnoexcuse



Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6028
GPA: 3.82

Re: If x, y, and z are positive integers, is x+y divisible by 5? 1) x+z is
[#permalink]
Show Tags
24 Aug 2017, 01:27
=> Consider 1) & 2) x = 1, y = 1, z = 4 : x + y is not divisible by 5 x = 5, y = 5, z = 0 : x + y is divisible by 5 Ans: E
_________________
MathRevolution: Finish GMAT Quant Section with 10 minutes to spare The oneandonly World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy. "Only $99 for 3 month Online Course" "Free Resources30 day online access & Diagnostic Test" "Unlimited Access to over 120 free video lessons  try it yourself"



Intern
Joined: 29 Jul 2012
Posts: 15

Re: If x, y, and z are positive integers, is x+y divisible by 5? 1) x+z is
[#permalink]
Show Tags
24 Aug 2017, 11:28
Q1. When the Q says x, y, z are integers, shouldn't we take all as different numbers but all the explanations here have considered x equal to y to reach to the answers. So is it that, unless explicitly defined as unique there is no need to take different values. Because the Q also doesn't say explicitly that x, y, z can take any value.
Q2. Also under the assumption that they are all different, would E still be the right answer, based on the following: 2+8 & 7+8 both divisible by 5 but 2+7 is not 5+0 & 10+0 both divisible by 5 and so is 5+10



Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6028
GPA: 3.82

If x, y, and z are positive integers, is x+y divisible by 5? 1) x+z is
[#permalink]
Show Tags
Updated on: 06 Sep 2017, 20:47
ravjai81 wrote: Q1. When the Q says x, y, z are integers, shouldn't we take all as different numbers but all the explanations here have considered x equal to y to reach to the answers. So is it that, unless explicitly defined as unique there is no need to take different values. Because the Q also doesn't say explicitly that x, y, z can take any value.
Q2. Also under the assumption that they are all different, would E still be the right answer, based on the following: 2+8 & 7+8 both divisible by 5 but 2+7 is not 5+0 & 10+0 both divisible by 5 and so is 5+10 Answer to Q1 x, y, z might be same or x, y, z might be different. The point is that there two answers. Answer to Q2 The example you have shown are good enough to identify that both condition together are not sufficient.
_________________
MathRevolution: Finish GMAT Quant Section with 10 minutes to spare The oneandonly World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy. "Only $99 for 3 month Online Course" "Free Resources30 day online access & Diagnostic Test" "Unlimited Access to over 120 free video lessons  try it yourself"



Manager
Joined: 02 Aug 2015
Posts: 83

Re: If x, y, and z are positive integers, is x+y divisible by 5? 1) x+z is
[#permalink]
Show Tags
30 Aug 2017, 00:10
Luckisnoexcuse wrote: (1) tells us x,z can take (0,5),(5,0).... also no information about y..not sufficient (2) tells us y,z can take (0,5),(5,0).... also no information about x..not sufficient on combining x,y can take (0,0) or (5,5) ...not sufficient E Hey mate, though your answer is correct, I would like to point out that 0 cannot be considered as the question stems says x,y, and z are positive integers. Appears Luckisnoexcuse got lucky! Cheers!



Intern
Joined: 19 Nov 2016
Posts: 7

Re: If x, y, and z are positive integers, is x+y divisible by 5? 1) x+z is
[#permalink]
Show Tags
12 Dec 2017, 17:18
MathRevolution wrote: => Consider 1) & 2)
x = 1, y = 1, z = 4 : x + y is not divisible by 5 x = 5, y = 5, z = 0 : x + y is divisible by 5
Ans: E Is 0 a positive number? I thought that it is not?



Math Expert
Joined: 02 Sep 2009
Posts: 47983

Re: If x, y, and z are positive integers, is x+y divisible by 5? 1) x+z is
[#permalink]
Show Tags
12 Dec 2017, 20:25




Re: If x, y, and z are positive integers, is x+y divisible by 5? 1) x+z is &nbs
[#permalink]
12 Dec 2017, 20:25






