gmatprep-1

This topic has expert replies
Source: — Problem Solving |

Legendary Member
Posts: 2467
Joined: Thu Aug 28, 2008 6:14 pm
Thanked: 331 times
Followed by:11 members

by cramya » Sun Dec 28, 2008 10:40 am
Key to these problems are working wiht extreme values

.1 = 1/10
.9 = 9/10

1.1 = 1 1/10 = 11/10

19/10


Stmt I

r/s will always be less than 1 since numerator bigger than denominator so fractions value has to be less than 1

must be true

Stmt II and III could be true but not must be true

rs = 9/10 * 11/10 <1
rs = 9/10 * 19/10 > 1

r-s = 1.1 - .9 <1
r-s = 1.8 - .2 >1

Hope this helps!

Legendary Member
Posts: 833
Joined: Mon Aug 04, 2008 1:56 am
Thanked: 13 times

by vivek.kapoor83 » Sun Dec 28, 2008 10:59 am
i apporched the same way..but was able to get 2nd choice alwatys <1.. :oops:

Legendary Member
Posts: 2467
Joined: Thu Aug 28, 2008 6:14 pm
Thanked: 331 times
Followed by:11 members

by cramya » Sun Dec 28, 2008 11:01 am
Pick different combinations of extremes from each of the ranges. This way it is less likely we miss out.

Also I have found converting these to fractions much easier to work with rather than working wiht decimal multiplication.

Good luck!

Legendary Member
Posts: 833
Joined: Mon Aug 04, 2008 1:56 am
Thanked: 13 times

by vivek.kapoor83 » Sun Dec 28, 2008 11:04 am
cramya,
u r guru....im v poor in DS....i scored 47 in Q...despite this...would be more then thankful if u can give me some tips regarding DS...i want Q to be 50...coz my V is weak and u can see my approach was rite..but i committed some silly errors..pls give me some tips for DS only...ur champ man !!!!!!!!!!!!!!!!!

Senior | Next Rank: 100 Posts
Posts: 37
Joined: Wed Sep 17, 2008 8:17 pm
Location: India
Thanked: 4 times

by Sachindh » Sun Dec 28, 2008 10:55 pm
Answer is A as statement i is always true where as other may or may not true.

I agree with you(Vivek). Cramya is guru.. He explain also very nicely.
Thanks

Legendary Member
Posts: 621
Joined: Wed Apr 09, 2008 7:13 pm
Thanked: 33 times
Followed by:4 members

by vittalgmat » Sun Dec 28, 2008 11:10 pm
Agreed guys.. Cramya knows the subject well and also takes pains in all the posts to explain well.. Hats off to u.

And, I am also kinda weak in DS. esp number prop- absolute, inequalities, divisiblity.

So I have searched for posts on BTG in these areas, bookmarked them according to categories and now I am going thru them making notes and listing the approaches and generalizing it..

I am seeing some +ve results by doing this.

Just my 2 cents.

HT Helps
-V

Legendary Member
Posts: 2467
Joined: Thu Aug 28, 2008 6:14 pm
Thanked: 331 times
Followed by:11 members

by cramya » Sun Dec 28, 2008 11:28 pm
And, I am also kinda weak in DS. esp number prop- absolute, inequalities, divisiblity

Vittal,
This should be used to be. I have seen some good posts in these topics from you recently.
I am seeing some +ve results by doing this.
I agree with Vittal on the fact that searching this forum for specific topics and taking notes of the various approaches from the experts pays rich dividends. Understanding the concepts and what to do and what not to do is more important than a specific problem. The actual problems posted here may never show up ion the real GMAT but the concepts/takeaways definitely yes -> can be used for other problems on the real test...


Thanks guys for the kind words! We are all here to help each other and enjoy each other's success.

Good luck!

Regards,
Cramya