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 →

gmat prep question

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Master | Next Rank: 500 Posts
Posts: 144
Joined: Wed Feb 07, 2007 4:13 pm
by yvonne12 » Sun Apr 15, 2007 5:40 pm
for any positive N, the length of N is defined as the number of prime factors where the product is n. For example the length of 75 is 3 since 75=3x5x5. How many 2 digit pos. intehers has length 6?

Could someone show me step by step on how to approach this kind of question? I cant come up with a strategy to figure this out quickly and less than a minute.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Problem Solving |
Senior | Next Rank: 100 Posts
Posts: 46
Joined: Sun Mar 04, 2007 6:27 am

by Tame the CAT » Sun Apr 15, 2007 6:09 pm
There should only be 2 numbers with a length of 6 as described in the question.

I tried 2^6 and got 64
Then I tried 2^5*3 and got 96

There are no more combinations of 6 prime numbers that would give me a two digit number.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Master | Next Rank: 500 Posts
Posts: 135
Joined: Tue Feb 27, 2007 7:21 pm
Thanked: 2 times

by rajesh_ctm » Sun Apr 15, 2007 7:35 pm
From the answer choices, you can figure out that there are not many such numbers possible. So listing down all the possible numbers would be a good strategy.

First find out what is the minimum number which has 6 prime factors. That will be 2X2X2X2X2X2 = 64

Now you can get the next greater number which will have 6 prime factors by increasing one factor from 2 to 3 (next possible prime number). So the next number is 2X2X2X2X2X3 = 96

If you further increase any factor (2 to 3 or 3 to 4), the result will cross 100, so 2 is the answer.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Legendary Member
Posts: 559
Joined: Tue Mar 27, 2007 1:29 amFollowed by: 2 members
Thanked: 5 times

by Cybermusings » Mon Apr 16, 2007 4:48 am
2*2*2*2*2*2 = 64

and 2*2*2*2*2*3 = 96

If you try susbstituting 3 for 2 any further we will move on to 3 digit numbers.

Hence answer is only 2 such double digit numbers exist
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1