BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

kaplan problem solving

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
User avatar
Master | Next Rank: 500 Posts
Posts: 447
Joined: Sun Apr 22, 2012 7:13 am
Thanked: 46 times
Followed by:13 members
GMAT Score:700

kaplan problem solving

by hemant_rajput » Mon Jun 24, 2013 8:05 am
Three is the largest number that can be divided evenly into 27 and the positive integer x, while 10 is the largest number that can be divided evenly into both 100 and x. Which of the following is the largest possible number that could be divided into x and 2,100?
a.30
b.70
c.210
d.300
e.700

[spoiler]OA:C[/spoiler]
what does it mean when you say 3 divide evenly into 27 and x?
I'm no expert, just trying to work on my skills. If I've made any mistakes please bear with me.
Top
Source: — Problem Solving |

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 16207
Joined: Mon Dec 08, 2008 6:26 pm
Location: Vancouver, BC
Thanked: 5254 times
Followed by:1268 members
GMAT Score:770

by Brent@GMATPrepNow » Mon Jun 24, 2013 8:14 am
hemant_rajput wrote:Three is the largest number that can be divided evenly into 27 and the positive integer x, while 10 is the largest number that can be divided evenly into both 100 and x. Which of the following is the largest possible number that could be divided into x and 2,100?
a.30
b.70
c.210
d.300
e.700

[spoiler]OA:C[/spoiler]
what does it mean when you say 3 divide evenly into 27 and x?
what does it mean when you say 3 divide evenly into 27 and x?
The wording here could be improved. The GMAT would never write "x divides evenly into y" since this could give one the impression that y divided by x must be an even number.
In everyday, informal speech, saying that x divides evenly into y is the same as saying that x is a divisor of y.

For this question, the GMAT test-makers would probably write something like "3 is greatest common divisor of x and 27"


A fast approach here is to use the process of elimination (POE).

E) Can x=700? No - otherwise the greatest common divisor of x and 100 would be 100 (where the question tells us that the GCD of x and 100 is 10)

D) Can x=300? No - otherwise the greatest common divisor of x and 100 would be 100 (where the question tells us that the GCD of x and 100 is 10)

C) Can x=210? Sure, the GCD of 210 and 27 is 3, and the GCD of 210 and 100 is 10
SO, if x=210, then the GCD of x and 2100 will be 210
The answer is C

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
Image
Top
User avatar
Master | Next Rank: 500 Posts
Posts: 447
Joined: Sun Apr 22, 2012 7:13 am
Thanked: 46 times
Followed by:13 members
GMAT Score:700

by hemant_rajput » Mon Jun 24, 2013 8:24 am
thanks Brent.

when we say x divides y evenly, can it also mean that y is even no?
I'm no expert, just trying to work on my skills. If I've made any mistakes please bear with me.
Top

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 16207
Joined: Mon Dec 08, 2008 6:26 pm
Location: Vancouver, BC
Thanked: 5254 times
Followed by:1268 members
GMAT Score:770

by Brent@GMATPrepNow » Mon Jun 24, 2013 8:28 am
hemant_rajput wrote:thanks Brent.

when we say x divides y evenly, can it also mean that y is even no?
No, we can't conclude that y is even. For example, we could say that 3 divides evenly into 15.

As I said, though, an official GMAT question would never say "divides evenly into"

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
Image
Top
Post new topic Post Reply
• Page 1 of 1