Summer is Coming! Join the Game of Timers Competition to Win Epic Prizes. Registration is Open. Game starts Mon July 1st.

 It is currently 20 Jul 2019, 01:04 ### 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

#### Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.  # If a and b are positive integers, what is the value of the product ab?

Author Message
TAGS:

### Hide Tags

Board of Directors D
Joined: 01 Sep 2010
Posts: 3421
If a and b are positive integers, what is the value of the product ab?  [#permalink]

### Show Tags

5
Top Contributor
16 00:00

Difficulty:   5% (low)

Question Stats: 80% (01:01) correct 20% (01:33) wrong based on 508 sessions

### HideShow timer Statistics If a and b are positive integers, what is the value of the product ab ?

(1) The least common multiple of a and b is 48.

(2) The greatest common factor of a and b is 4.

_________________
Math Expert V
Joined: 02 Aug 2009
Posts: 7764
Re: If a and b are positive integers, what is the value of the product ab?  [#permalink]

### Show Tags

11
1
8
carcass wrote:
If a and b are positive integers, what is the value of the product ab ?

(1) The least common multiple of a and b is 48.

(2) The greatest common factor of a and b is 4.

Whenever a Q talks of product, LCM and HCF of two numbers .. most likely it will deal with the formula..
Product = LCM * HCF

the two statements give LCM and HCF separately ..
so COMBINED we can get the product as 48*4
suff
C
_________________
##### General Discussion
CEO  V
Joined: 12 Sep 2015
Posts: 3852
If a and b are positive integers, what is the value of the product ab?  [#permalink]

### Show Tags

2
Top Contributor
5
carcass wrote:
If a and b are positive integers, what is the value of the product ab ?

(1) The least common multiple of a and b is 48

(2) The greatest common factor of a and b is 4

Target question: What is the value of the product ab?

Statement 1: The least common multiple of a and b is 48
Let's TEST some numbers.
There are several values of a and b that satisfy statement 1. Here are two:
Case a: a = 1 and b = 48. In this case, ab = (1)(48) = 48
Case b: a = 2 and b = 48. In this case, ab = (2)(48) = 96
Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT

Statement 2: The greatest common factor (aka divisor) of a and b is 4
Let's TEST some numbers (again).
There are several values of a and b that satisfy statement 2. Here are two:
Case a: a = 8 and b = 4. In this case, ab = (8)(4) = 32
Case b: a = 4 and b = 4. In this case, ab = (4)(4) = 16
Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT

Statements 1 and 2 combined
--------ASIDE----------------------
There's a nice rule that says:
(greatest common divisor of x and y)(least common multiple of x and y) = xy
Example: x = 10 and y = 15
Greatest common divisor of 10 and 15 = 5
Least common multiple of 10 and 15 = 30
Notice that these values satisfy the above rule, since (5)(30) = (10)(15)
--------BACK TO THE QUESTION! ----------------------

When we apply the above rule, we get: (4)(48) = ab
So, ab = 192
Since we can answer the target question with certainty, the combined statements are SUFFICIENT

RELATED VIDEO

_________________
Manager  S
Joined: 20 Jul 2018
Posts: 87
GPA: 2.87
Re: If a and b are positive integers, what is the value of the product ab?  [#permalink]

### Show Tags

(GCF)(LCM)=Product
So
From statemnt 1 we get LCM and from statement 2 we get GCF.
So ab=48*4

Posted from my mobile device
_________________
Hasnain Afzal

"When you wanna succeed as bad as you wanna breathe, then you will be successful." -Eric Thomas
ISB School Moderator G
Joined: 08 Dec 2013
Posts: 529
Location: India
Concentration: Nonprofit, Sustainability
GMAT 1: 630 Q47 V30 WE: Operations (Non-Profit and Government)
Re: If a and b are positive integers, what is the value of the product ab?  [#permalink]

### Show Tags

carcass wrote:
If a and b are positive integers, what is the value of the product ab ?

(1) The least common multiple of a and b is 48.

(2) The greatest common factor of a and b is 4.

LCM(a,b) * HCF(a*b) = a*b

Option C
_________________
Kindly drop a '+1 Kudos' if you find this post helpful.

GMAT Math Book

-I never wanted what I gave up
I never gave up what I wanted- Re: If a and b are positive integers, what is the value of the product ab?   [#permalink] 26 Jun 2019, 23:40
Display posts from previous: Sort by

# If a and b are positive integers, what is the value of the product ab?  