It is currently 23 Sep 2020, 07:05

### 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

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

# a > 0

Author Message
TAGS:
Founder
Joined: 18 Apr 2015
Posts: 13344
Followers: 288

Kudos [?]: 3382 [0], given: 12176

a > 0 [#permalink]  08 Sep 2018, 23:57
Expert's post
00:00

Question Stats:

81% (00:23) correct 18% (00:27) wrong based on 37 sessions
$$a > 0$$

 Quantity A Quantity B $$5ab$$ $$10ab$$

A) Quantity A is greater.
B) Quantity B is greater.
C) The two quantities are equal.
D) The relationship cannot be determined from the information given.

Kudos for R.A.E
[Reveal] Spoiler: OA

_________________

Need Practice? 20 Free GRE Quant Tests available for free with 20 Kudos
GRE Prep Club Members of the Month: Each member of the month will get three months free access of GRE Prep Club tests.

GRE Instructor
Joined: 10 Apr 2015
Posts: 3830
Followers: 148

Kudos [?]: 4479 [1] , given: 69

Re: a > 0 [#permalink]  09 Sep 2018, 06:53
1
KUDOS
Expert's post
Carcass wrote:
$$a > 0$$

 Quantity A Quantity B $$5ab$$ $$10ab$$

We can solve this question using matching operations

Given:
Quantity A: 5ab
Quantity B: 10ab

Since a is POSITIVE, we can safely divide both quantities by a to get:
Quantity A: 5b
Quantity B: 10b

We can also safely divide both quantities by 5 to get:
Quantity A: b
Quantity B: 2b

Finally, let's subtract b from both quantities to get:
Quantity A: 0
Quantity B: b

Since b could be positive, negative or zero, the correct answer is D

RELATED VIDEO FROM OUR COURSE

_________________

Brent Hanneson – Creator of greenlighttestprep.com
If you enjoy my solutions, you'll like my GRE prep course.

Founder
Joined: 18 Apr 2015
Posts: 13344
Followers: 288

Kudos [?]: 3382 [0], given: 12176

Re: a > 0 [#permalink]  09 Sep 2018, 07:50
Expert's post
ab or 5 ab (simplified), which one is greatest ??

we do not have any information about b. The two statements are not sufficient to determine which one is the biggest.

Regards
_________________

Need Practice? 20 Free GRE Quant Tests available for free with 20 Kudos
GRE Prep Club Members of the Month: Each member of the month will get three months free access of GRE Prep Club tests.

Intern
Joined: 27 Aug 2018
Posts: 36
Followers: 0

Kudos [?]: 21 [0], given: 7

Re: a > 0 [#permalink]  10 Sep 2018, 09:07
B can be any value, so the answer is D
Intern
Joined: 13 Nov 2018
Posts: 36
Followers: 0

Kudos [?]: 15 [0], given: 0

Re: a > 0 [#permalink]  17 Nov 2019, 19:21
I think the answer is B. We do not need the value of b as it can be cancelled out. Since b is on both sides whatever it’s value is it will cancel out. Leaving the side B greater than A.

Posted from my mobile device
GRE Instructor
Joined: 10 Apr 2015
Posts: 3830
Followers: 148

Kudos [?]: 4479 [0], given: 69

Re: a > 0 [#permalink]  18 Nov 2019, 05:35
Expert's post
qamarsabir wrote:
I think the answer is B. We do not need the value of b as it can be cancelled out. Since b is on both sides whatever it’s value is it will cancel out. Leaving the side B greater than A.

Posted from my mobile device

When we talk about "cancelling out" variables, we must be clear what we're actually doing.
To get "cancel out" the variable b, we need to divide both quantities by b.
However, since we don't know whether b is positive, negative or zero, we can't just divide both quantities by b.

For example, if b = 0, then the two quantities are equal.
If b = -1, then quantity A is greater
And, if b = 1, then quantity B is greater

Cheers,
Brent
_________________

Brent Hanneson – Creator of greenlighttestprep.com
If you enjoy my solutions, you'll like my GRE prep course.

Re: a > 0   [#permalink] 18 Nov 2019, 05:35
Display posts from previous: Sort by