GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 17 Dec 2018, 09:18

Close

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
Your Progress

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.

Close

Request Expert Reply

Confirm Cancel
Events & Promotions in December
PrevNext
SuMoTuWeThFrSa
2526272829301
2345678
9101112131415
16171819202122
23242526272829
303112345
Open Detailed Calendar
  • 10 Keys to nail DS and CR questions

     December 17, 2018

     December 17, 2018

     06:00 PM PST

     07:00 PM PST

    Join our live webinar and learn how to approach Data Sufficiency and Critical Reasoning problems, how to identify the best way to solve each question and what most people do wrong.
  • R1 Admission Decisions: Estimated Decision Timelines and Chat Links for Major BSchools

     December 17, 2018

     December 17, 2018

     10:00 PM PST

     11:00 PM PST

    From Dec 5th onward, American programs will start releasing R1 decisions. Chat Rooms: We have also assigned chat rooms for every school so that applicants can stay in touch and exchange information/update during decision period.

Finding the number of unique factors | Explained in a 2-minutes video

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Manager
Manager
User avatar
S
Joined: 19 Feb 2010
Posts: 177
Finding the number of unique factors | Explained in a 2-minutes video  [#permalink]

Show Tags

New post 23 Feb 2018, 16:56
Dear All,

Hope this finds you well.

Here is a short video for finding the number of unique factors of any number. The concept explained will help you solve questions such as the following in less than a minute.

Q. How many unique positive integers are factors of 20^10?
(Answer: 231)



Hope this helps.

All the best!
Experts' Global Team
_________________

GMAT Preparation Online- World's Most Complete GMAT Prep Program | Gain 7-days demo access (includes a full length test)

Intern
Intern
User avatar
B
Joined: 15 Sep 2017
Posts: 23
GMAT 1: 750 Q50 V42
GPA: 3.5
Re: Finding the number of unique factors | Explained in a 2-minutes video  [#permalink]

Show Tags

New post 24 Feb 2018, 11:22
Nice Video!

I'd like to just to add something to this topic:

One way the test can trick you is by not showing the primes behind the number.
For example (easy one):
399 is 133 x 3.
If you do (1+1) x (1+1), you get 4 factors, but actually 399 is 19 x 7 x 2 and it has (1+1) x (1+1) x (1+1) = 8 factors

Additionally, if the question asks you the number of factors of x = a^3 x b^4 x c^5, you can not assume that it is (3+1) x (4+1) x (5+1) = 120, as it could very well be that a = b = c and, therefore, x = a^12 and the number of factors is (12+1) = 13
_________________

"Revenge is a dish best served cold"

Manager
Manager
User avatar
S
Joined: 19 Feb 2010
Posts: 177
Re: Finding the number of unique factors | Explained in a 2-minutes video  [#permalink]

Show Tags

New post 24 Feb 2018, 11:33
Thanks for the reply, Daniel.

Yes, the bases involved need to be all different and prime.

These aspects have been covered at 00:20 and 01:20 In the video.

Thanks a ton for your contribution.

All the best!
Experts' Global Team

Sent from my SM-N950F using GMAT Club Forum mobile app
_________________

GMAT Preparation Online- World's Most Complete GMAT Prep Program | Gain 7-days demo access (includes a full length test)

GMAT Club Bot
Re: Finding the number of unique factors | Explained in a 2-minutes video &nbs [#permalink] 24 Feb 2018, 11:33
Display posts from previous: Sort by

Finding the number of unique factors | Explained in a 2-minutes video

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


Copyright

GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.