Help please!!!!!!!!!!!

Expert replies

Previous Topic Next Topic

abuc0112: Junior | Next Rank: 30 Posts; Posts: 14; Joined: Fri Jun 18, 2010 8:52 am

by abuc0112 » Wed Sep 07, 2011 7:22 pm

If x is an integer and y = 3x + 2, which of the following CANNOT be a divisor of y ?
(A) 4
(B) 5
(C) 6
(D) 7
(E) 8

Like this post

Source: Beat The GMAT — Problem Solving | Wed Sep 07, 2011 7:22 pm

cans: Legendary Member; Posts: 1309; Joined: Mon Apr 04, 2011 5:34 amFollowed by: 123 members; Location: India; Thanked: 310 times; GMAT Score:750

by cans » Wed Sep 07, 2011 7:41 pm

IMO C
y=3x+2.
(3x+2)/6 will never be an integer. because 3x can be divisible by 6 when x is even. but 2 can't be divisible by 6.

If my post helped you- let me know by pushing the thanks button

Contact me about long distance tutoring!
[email protected]

Cans!!

Like this post

pemdas: Legendary Member; Posts: 1084; Joined: Fri Apr 15, 2011 2:33 pmFollowed by: 21 members; Thanked: 158 times

by pemdas » Wed Sep 07, 2011 9:12 pm

two answer choices are odd primes (5 and 7), hence divisibility of (3x+2) by these primes should allow for x to be odd integer

for the answer choice (4) if (3x+2) is divisible by 2 and greater than 2 then it must be divisible by 4

the same for answer choice (8) if (3x+2) is divisible by 4 and greater than 4 it must be divisible by 8

we are left with answer choice (6)

abuc0112 wrote:If x is an integer and y = 3x + 2, which of the following CANNOT be a divisor of y ?
(A) 4
(B) 5
(C) 6
(D) 7
(E) 8

Success doesn't come overnight!

Like this post

edvhou812: Master | Next Rank: 500 Posts; Posts: 143; Joined: Sat Nov 06, 2010 9:06 pmFollowed by: 1 member; Thanked: 10 times

by edvhou812 » Thu Sep 08, 2011 1:16 am

You can also plug in numbers for x:

A: x=6 3x+2=20 (Out)
B: x=1 3x+2=5 (Out)
C: Hold. Can tell it will take a lot of plugging in...
D: x=11 3x+2=35 (Out)
E: x=2 3x+2=8 (Out)

If four are out, it must be the only one that remains. Answer: C

I don't know what to say, really. Three minutes to the biggest battle of our professional lives. You find out life's this game of inches, so is football. Because in either game - life or football - the margin for error is so small. I mean, one half a step too late or too early and you don't quite make it. One half second too slow, too fast and you don't quite catch it. I'll tell you this, in any fight it's the guy whose willing to die whose gonna win that inch. That's football guys, that's all it is. Now, what are you gonna do?

Like this post

navami: Legendary Member; Posts: 540; Joined: Sat Dec 20, 2008 7:24 pmFollowed by: 6 members; Thanked: 37 times

by navami » Thu Sep 08, 2011 6:09 am

(3x+2)/6 is never integer
IF X IS EVEN :
3X is divisible by 6
but 3X+2 will give 2 as reminder

IF X is oDD:
3x = ODD
3X+ 2 = ODD
Hence can not be divisible by 6

This time no looking back!!!
Navami

Like this post

Post new topic Post Reply

• Page 1 of 1

GMAT Course Reviews

559 reviews

1168 reviews

431 reviews

359 reviews

147 reviews

5/5

5 Star (560 Reviews)

"Target Test Prep is the closest to the official version of the GMAT exam, about 99% accuracy in terms of the quality and quantity of information. The course has excellently created singular sets of focused lessons and tests for every possible topic that one could come across in the official GMAT exam."

"The TTP course maximizes the efficiency of the time you spend studying. It will take time and effort but I could almost guarantee that if you complete the course exactly as it is laid out you will get an amazing score. They also have a very responsive team willing to help with any questions you might have."

"TTP has two things that I think no other test prep company offers: A teaching approach that reinforces understanding and an attitude that will give you the mental preparedness needed to succeed on the test. TTP gives you a deep understanding of the concept you need to know while teaching you how to think."

Write a Review