Events & Promotions
|
|
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
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Nov 2007:30 AM PST
-08:30 AM PST
Learn what truly sets the UC Riverside MBA apart and how it helps in your professional growth
Nov 2211:00 AM IST
-01:00 PM IST
Do RC/MSR passages scare you? e-GMAT is conducting a masterclass to help you learn – Learn effective reading strategies Tackle difficult RC & MSR with confidence Excel in timed test environment- Nov 23
11:00 AM IST
-01:00 PM IST
Attend this free GMAT Algebra Webinar and learn how to master the most challenging Inequalities and Absolute Value problems with ease. 
Nov 2510:00 AM EST
-11:00 AM EST
Prefer video-based learning? The Target Test Prep OnDemand course is a one-of-a-kind video masterclass featuring 400 hours of lecture-style teaching by Scott Woodbury-Stewart, founder of Target Test Prep and one of the most accomplished GMAT instructors.
![If [x] denotes the greatest integer less than or equal to x for any nu](/forum/styles/gmatclub_light/imageset/icon_post_target_unread.svg "If [x] denotes the greatest integer less than or equal to x for any nu"){kind=icon}
31 Oct 2014, 02:43
Kudos
Bookmarks
A
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
95%
(hard)
Question Stats:
44% (02:18) correct
56%
(02:25)
wrong
based on 252
sessions
History
Date
Time
Result
Not Attempted Yet
If [x] denotes the greatest integer less than or equal to x for any number x, is [a]+[b]=1?
(1) ab=2.
(2) 0<a<b<2.
Source: GCT M28-56
(1) ab=2.
(2) 0<a<b<2.
Source: GCT M28-56
Experience GMAT Club Test Questions
Yes, you've landed on a GMAT Club Tests question
Craving more? Unlock our full suite of GMAT Club Tests here
Want to experience more? Get a taste of our tests with our free trial today
Rise to the challenge with GMAT Club Tests. Happy practicing!
31 Oct 2014, 03:45
Kudos
Bookmarks
Nice question!
[a]+[b]=1 can happen if one value is negative and one positive OR if one value is 0 and the other is 1.
A - ab = 2
if both a and b are negative - then [a]+[b]=1 is not possible
If a and b are positive - can it result in one value being 0 (i.e. 0<a<1) and the other 0 (1<b<2)
This is impossible as if 1<b<2 then it has to be multiplied by a number larger than 1 to give 2.
But if a is larger than one then [a]+[b]=2.
So if ab=2 then it cannot happen that [a]+[b]=1 and A is SUFFICIENT
B - 0<a<b<2
If 0<a<1 and 1<b<2 then [a]+[b]=1 is true
if 0<a<1 and a<b<1 then [a]+[b]=1 is not true
So we cannot conclude and B is NOT SUFFICIENT
[a]+[b]=1 can happen if one value is negative and one positive OR if one value is 0 and the other is 1.
A - ab = 2
if both a and b are negative - then [a]+[b]=1 is not possible
If a and b are positive - can it result in one value being 0 (i.e. 0<a<1) and the other 0 (1<b<2)
This is impossible as if 1<b<2 then it has to be multiplied by a number larger than 1 to give 2.
But if a is larger than one then [a]+[b]=2.
So if ab=2 then it cannot happen that [a]+[b]=1 and A is SUFFICIENT
B - 0<a<b<2
If 0<a<1 and 1<b<2 then [a]+[b]=1 is true
if 0<a<1 and a<b<1 then [a]+[b]=1 is not true
So we cannot conclude and B is NOT SUFFICIENT
31 Oct 2014, 03:54
Kudos
Bookmarks
If [x] denotes the greatest integer less than or equal to x for any number x, is [a] + [b] = 1 ?
Given that some function [] rounds DOWN a number to the nearest integer. For example [1.5]=1, [2]=2, [-1.5]=-2, ...
(1) ab = 2. First of all this means that a and b are of the same sign.
If both are negative, then the maximum value of [a] + [b] is -2, for any negative a and b. So, this case is out.
If both are positive, then in order [a] + [b] = 1 to hold true, must be true that [a]=0 and [b]=1 (or vise-versa). Which means that \(0\leq{a}<1\) and \(1\leq{b}<2\) (or vise-versa). But in this case ab cannot be equal to 2. So, this case is also out.
We have that the answer to the question is NO. Sufficient.
(2) 0 < a < b < 2. If a=1/2 and b=1, then [a] + [b] = 0 + 1 = 1 but if a=1/4 and b=1/2, then [a] + [b] = 0 + 0 = 0. Not sufficient.
Answer: A.
THIS QUESTION IS DISCUSSED HERE: new-set-number-properties-149775-60.html#p1205389
Given that some function [] rounds DOWN a number to the nearest integer. For example [1.5]=1, [2]=2, [-1.5]=-2, ...
(1) ab = 2. First of all this means that a and b are of the same sign.
If both are negative, then the maximum value of [a] + [b] is -2, for any negative a and b. So, this case is out.
If both are positive, then in order [a] + [b] = 1 to hold true, must be true that [a]=0 and [b]=1 (or vise-versa). Which means that \(0\leq{a}<1\) and \(1\leq{b}<2\) (or vise-versa). But in this case ab cannot be equal to 2. So, this case is also out.
We have that the answer to the question is NO. Sufficient.
(2) 0 < a < b < 2. If a=1/2 and b=1, then [a] + [b] = 0 + 1 = 1 but if a=1/4 and b=1/2, then [a] + [b] = 0 + 0 = 0. Not sufficient.
Answer: A.
THIS QUESTION IS DISCUSSED HERE: new-set-number-properties-149775-60.html#p1205389
