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

Redeem
TTP OnDemand GMAT Video Course
Featured Course

Target Test Prep GMAT OnDemand

Scott Woodbury-Stewart’s private virtual classroom — 400 hours of master-class video lessons for the GMAT Focus Edition.

  • 715+ score guarantee — highest in the industry (99th percentile)
  • 52 chapters · 1,500+ lessons · 4,000+ practice questions
  • 400 hours of video · 1,500+ instructor-led HD smartboard lessons
  • 300,000+ students accepted to Harvard, Stanford, Wharton, Booth & Sloan & more
  • 24/7 live support + weekly Zoom office hours with GMAT instructors
  • TTP AI Assist — 24/7 AI-powered virtual tutor for instant help
  • 1,200+ flashcards + AI-powered study assistant & daily calendar
  • OnDemand, LiveTeach & GMAT Bootcamp formats available
  • Also: GRE, SAT Math & Executive Assessment courses
  • MBA Admissions Consulting now available
  • 🏆 2025 EdTech Breakthrough Award: Test Prep Solution Provider of the Year
  • 200,000+ students served
  • 5-day free trial — $0 to start, no auto-billing, cancel anytime
★★★★★ 5.0 (559 reviews)
130-pt guarantee
$0 to start then $127/mo
Start Free 5-Day Trial Read 559 Reviews →

Prime Factors

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Senior | Next Rank: 100 Posts
Posts: 62
Joined: Thu Jul 03, 2008 4:52 am
by [email protected] » Tue Jul 22, 2008 6:41 am
Can someone please tell me how to answer this question, the books explanation is shocking!!

If a and b are positive integers, is a a multiple of b?

(1) Every distinct prime factor of b is also a distinct prime factor of a

(2)Every factor of b is also a factor of a

Thanks in advance!
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Data Sufficiency |
Master | Next Rank: 500 Posts
Posts: 102
Joined: Sat Mar 15, 2008 4:03 am
Thanked: 4 times

by wilderness » Tue Jul 22, 2008 8:22 am
IMHO, The answer is B.

Look at it in this way.

First consider 2).
- Since every number is a factor of itself, b is a factor of b.
- It is given that every factor of b is a factor of a.

from i) and ii) b is a factor of A. Therefore A is a multiple of B.

1) is not sufficient because what about the prime factors that are repeated. two number having the same prime factors does not mean they are multiple of each other.
e.g. 12 and 18 have the same prime factor 2 and 3 but neither is the multiple of the other. But 6 and 12 have same prime factors but 12 is a multiple of 6.

Guys, please correct me if my explanation is misleading. Would it have made a difference had the the word distinct was been there ?
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Newbie | Next Rank: 10 Posts
Posts: 5
Joined: Mon Jun 16, 2008 9:54 pm

by classic » Tue Jul 22, 2008 11:09 am
what if a=b
Is a still a factor of b
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Senior | Next Rank: 100 Posts
Posts: 58
Joined: Fri Jul 11, 2008 5:00 am
Thanked: 4 times

by Canman » Tue Jul 22, 2008 11:17 am
Sure- every number will have at least 1 and itself as a factor. So if a=b then a can be a factor of b.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1