GMAT Math

I'm referencing the problems where they tell you N is an integer and you are given information and are asked to determine if N is divisible by some number. Are there any web resources that do a good job of explaining/reviewing this or is it pretty much necessary that the MGMAT Number Properties book should be purchased?

I learned pretty much solely from this website, but if that does not work out, Manhattan probably your best bet.

Hey, thanks for the reply. I think I'm going to just break down and buy the book. Its under 30 dollars, and it is definitely my weakest area, so it can't hurt to purchase it. Thanks for taking the time to reply.

osirus0830 wrote:Hey, thanks for the reply. I think I'm going to just break down and buy the book. Its under 30 dollars, and it is definitely my weakest area, so it can't hurt to purchase it. Thanks for taking the time to reply.

I would be extremely grateful if you wrote a short review on the book once you have gone through it.

I just ordered it from amazon. I will post a review in this forum as soon as I go through it.

hey Osirus ,
i am about to start with # properties. If you could provide ur experience as to how u found MGMAT # properties book. coz even i am weak in this topic

Waiting for your valuable pointers .

thanks

https://www.platinumgmat.com/gmat_study_ ... properties
I think this link will surely add up to ur knowledge for number properties..

Hey as already written,for number properties the best book is the Manhattan GMAT guide.
Some links on net may also help you but if you want to study the topic in conjunction ,the best bet in my opinion would still be MGMAT.

Also,for divisibility rules you can refer these links:-
https://mathforum.org/k12/mathtips/division.tips.html - Describes in details the divisibility concept.
https://en.wikipedia.org/wiki/Divisibility_rule - For reference purposes a divisibility chart is given.This can come in handy when revising in the last few days.

hey Shashank, thats good link - I see good material for Probability, was looking for...

gmattarget700 wrote:hey Shashank, thats good link - I see good material for Probability, was looking for...

Hey gmattarget700 u will surely get a lot of things related to GMAT maths or rather HS maths there..
I have collected few more links related to various topics..send me message whenever required..

Hey guys,

This may be a day late and a dollar short (it looks like the thread itself is about 8 months old), but I saw this near the top of the list and thought I'd chime in. Regarding number properties, I'd say that the best way to learn them is to identify them and apply them yourself. A few key points:

1) When the GMAT is testing large (i.e. 12^34) or abstract numbers (i.e. n^(x+1) - n^(x-1)) there's a good chance that number properties are in play. In these cases, see if you can establish a pattern. For example, I worked with a student on a question that included 2^x - 2^(x-2), and set that equal to a large number (3*2^17). Knowing that the question dealt with abstract and large numbers, I sought to find a pattern using small numbers: 2^3 - 2^1 = 6, which is 3(2^1). 2^4 - 2^2 = 12, which is 3(2^2), etc. By noting that there was a pattern - the difference is always 3 * the second term - I could easily solve this one.

2) It is more important to know that number properties exist than to memorize the property itself. By definition, these properties will always hold, so if you need to remember them, you can always prove them. For example, the number 7, when taken to exponents 1, 2, ...., n goes through the cycle: 7, 9, 3, 1, 7, 9, 3, 1, etc. But you don't need to memorize that pattern - as long as you know that "exponents yield pattern-driven units digits", you can rather quickly prove the pattern for each number to yourself, and save your mental energy when you study for other things.

3) Most importantly, number properties is more a state of mind than a list of rules. When you solve problems, see if you can find patterns between them, or use number properties to find a faster, smarter way to do it. The more you learn to think in those terms, the more you'll have a feel for number properties as a whole. The nice thing for the GMAT is that "number properties" includes a variety of individual numerical rules, so they can build the reward structure to reward higher-order thinking and not just memorization; the nice thing for you is that, once you buy in to the mindset, even the most complex math problems on the test are solvable by finding that pattern or mode of thinking that unlocks them.

Thanks to all for providing their insights ! Even I was curious about this topic.Any further tips on number properties will be helpful.