GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 12 Dec 2018, 20:12

### 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

## Events & Promotions

###### Events & Promotions in December
PrevNext
SuMoTuWeThFrSa
2526272829301
2345678
9101112131415
16171819202122
23242526272829
303112345
Open Detailed Calendar
• ### The winning strategy for 700+ on the GMAT

December 13, 2018

December 13, 2018

08:00 AM PST

09:00 AM PST

What people who reach the high 700's do differently? We're going to share insights, tips and strategies from data we collected on over 50,000 students who used examPAL.
• ### GMATbuster's Weekly GMAT Quant Quiz, Tomorrow, Saturday at 9 AM PST

December 14, 2018

December 14, 2018

09:00 AM PST

10:00 AM PST

10 Questions will be posted on the forum and we will post a reply in this Topic with a link to each question. There are prizes for the winners.

# If the LCM of two integers a, b (where b> a and a>1) is a*b, then whi

Author Message
TAGS:

### Hide Tags

Senior Manager
Joined: 13 Jun 2013
Posts: 275
If the LCM of two integers a, b (where b> a and a>1) is a*b, then whi  [#permalink]

### Show Tags

19 Nov 2014, 00:44
2
00:00

Difficulty:

25% (medium)

Question Stats:

70% (01:20) correct 30% (01:20) wrong based on 148 sessions

### HideShow timer Statistics

If the LCM of two integers a, b (where b> a and a>1) is a*b, then which of the following can not be true?

A. Both a and b can be Prime Numbers.
B. Both a and b can be consecutive integers.
C. All Prime factors of a must be Prime factors of b.
D. a and b do not share any Prime factors.
E. a and b do not have a common factor
SVP
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1825
Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)
Re: If the LCM of two integers a, b (where b> a and a>1) is a*b, then whi  [#permalink]

### Show Tags

19 Nov 2014, 01:04
manpreetsingh86 wrote:
If the LCM of two integers a, b (where b> a and a>1) is a*b, then which of the following can not be true?

A. Both a and b can be Prime Numbers.
B. Both a and b can be consecutive integers.
C. All Prime factors of a must be Prime factors of b.
D. a and b do not share any Prime factors.
E. a and b do not have a common factor

Say a = 2; b = 3; only option C contradicts

All Prime factors of a must be Prime factors of b

_________________

Kindly press "+1 Kudos" to appreciate

Manager
Status: I am not a product of my circumstances. I am a product of my decisions
Joined: 20 Jan 2013
Posts: 117
Location: India
Concentration: Operations, General Management
GPA: 3.92
WE: Operations (Energy and Utilities)
Re: If the LCM of two integers a, b (where b> a and a>1) is a*b, then whi  [#permalink]

### Show Tags

20 Nov 2014, 08:01
1
manpreetsingh86 wrote:
If the LCM of two integers a, b (where b> a and a>1) is a*b, then which of the following can not be true?

A. Both a and b can be Prime Numbers.
B. Both a and b can be consecutive integers.
C. All Prime factors of a must be Prime factors of b.
D. a and b do not share any Prime factors.
E. a and b do not have a common factor

If LCM of two numbers A and B is the product AB then both numbers are Co- prime.

( Co-prime numbers are any two numbers which have an HCF of 1 i.e. when two numbers have no common prime factor apart from the number 1).

Numbers that can be Co-Prime are :

1) Two consecutive natural numbers.
2) Two consecutive odd numbers.
3) Two prime numbers.
4) One prime number and the other a composite number such that the composite number is not a multiple of the prime number.

With above four statements it can be concluded that Options A, B, D and E are all true.

Only Option C cannot be true.
Director
Joined: 23 Jan 2013
Posts: 568
Schools: Cambridge'16
If the LCM of two integers a, b (where b> a and a>1) is a*b, then whi  [#permalink]

### Show Tags

18 Mar 2016, 03:06
a*b=LCM*GCF

a*b=LCM means GCF=1, so a and b are coprime numbers, i.e. do not share any factor except 1

C cannot be true
Senior Manager
Joined: 13 Oct 2016
Posts: 367
GPA: 3.98
Re: If the LCM of two integers a, b (where b> a and a>1) is a*b, then whi  [#permalink]

### Show Tags

20 Dec 2016, 07:03
manpreetsingh86 wrote:
If the LCM of two integers a, b (where b> a and a>1) is a*b, then which of the following can not be true?

A. Both a and b can be Prime Numbers.
B. Both a and b can be consecutive integers.
C. All Prime factors of a must be Prime factors of b.
D. a and b do not share any Prime factors.
E. a and b do not have a common factor

By definition, co-prime numbers are numbers which don't share any common factor EXCEPT 1 or which GCF is 1. C is fits perfectly but what about E?
We have: "a and b do not have a common factor". Co-primes don't share any prime factor, but they DO SHARE one common factor and that factor is 1. Hence E fits the bill too.
Non-Human User
Joined: 09 Sep 2013
Posts: 9143
Re: If the LCM of two integers a, b (where b> a and a>1) is a*b, then whi  [#permalink]

### Show Tags

24 Feb 2018, 00:16
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________
Re: If the LCM of two integers a, b (where b> a and a>1) is a*b, then whi &nbs [#permalink] 24 Feb 2018, 00:16
Display posts from previous: Sort by