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.

It appears that you are browsing the GMAT Club forum unregistered!

Signing up is free, quick, and confidential.
Join other 350,000 members and get the full benefits of GMAT Club

Registration gives you:

Tests

Take 11 tests and quizzes from GMAT Club and leading GMAT prep companies such as Manhattan GMAT,
Knewton, and others. All are free for GMAT Club members.

Applicant Stats

View detailed applicant stats such as GPA, GMAT score, work experience, location, application
status, and more

Books/Downloads

Download thousands of study notes,
question collections, GMAT Club’s
Grammar and Math books.
All are free!

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

Be extremely systematic. I make couples, starting with one, and counting up. You'll soon cover everything:

60:
1&60
2&30
3&20
4&15
5&12
6&10

By counting up on the low end, you cover everything on the high end as well. In this example, the next factor up from 6 is 10, and that's already there, and so is everything else above 10. This is better than randomly throwing out numbers until you hit them all.

Try it with a couple of examples that have lots of factors, like 24, 72, 36, 105.

Try it also with some variables: Name all the factors of 4p if p is a prime number.
4p:
1&4p
2&2p
4&p

Re: Counting factors of a number [#permalink]
22 Jul 2004, 11:55

saurya_s wrote:

Hi all How does one count the factors of a given number consdiering 1 and number itself. Thanks

Dear saurya_s, we(me and gravedigger) are working on a system of automated training which will contain easy and quick formulas for this and other things.

I know it is done using combinations and using binomial coefficients. For example for 6 (excluding 1 and 6) ie 2x3 is 2C0+2C1 or something like this but I am not sure exactly. There might be some one of us knowing it. Let's take an example how many salads can one make using- lettuce, cucumber, cabbage. Now salad can be made by selecting one of these at at time or 2 at a time or 3 at a time. So, it is 3C1+3C2+3c3= 2^3-1=7
as 3C0+3C1+3C2+3c3=(1+1)^3. Now 3C0 is one so, the answer is 2^3-1=7
Now can some one extend this for factors of number.
Best
S

Essay B for Stanford GSB will essentially ask you to explain why you’re doing what you’re doing. Namely, the essay wants to know, A) why you’re seeking...

The following pictures perfectly describe what I’ve been up to these days. MBA is an extremely valuable tool in your career, no doubt, just that it is also...