Search found 112 matches


Machines OG

Machine A produces bolts at a uniform rate of 120 every 40 seconds, and Machine B produces bolts at a uniform rate of 100 every 20 seconds. If the two machines run simultaneously, how many seconds will it take for them to produce a total of 200 bolts? Answer: By calculation, we find out that Machine...

by Thouraya

Sun Sep 18, 2011 12:10 am
Forum: Problem Solving
Topic: Machines OG
Replies: 8
Views: 2912

sum of consecutive integers

Expert help appreciated: (not sure what the OA is)


Is the sum of a series of n consecutive integers even?

(1) n=6
(2) The n digit number formed by the seriest is a multiple of nine

by Thouraya

Sat Sep 17, 2011 4:20 am
Forum: Data Sufficiency
Topic: sum of consecutive integers
Replies: 2
Views: 1000

Probability

A jar contains 3 red marbles and 2 blue marbles. If two marbles are selected at the same time, what is the probability that both marbles will be red?

How can I solve the above with the approach 1-Probability of None?

Thanks

by Thouraya

Sat Sep 17, 2011 12:51 am
Forum: Problem Solving
Topic: Probability
Replies: 2
Views: 977

@GMATGuruNY,

What if I want to solve the marbles problem with the approach 1-Probability None?

PS: i can't solve the Joshua/Jose problem with this approach because we have more than two choices?

Thank you so much

by Thouraya

Sat Sep 17, 2011 12:49 am
Forum: Problem Solving
Topic: Joshua and Jose
Replies: 14
Views: 2676

Hi,

Sorry I didn't understand this question. Can someone please elaborate on the answer? Thanks!

by Thouraya

Fri Sep 16, 2011 5:07 am
Forum: Problem Solving
Topic: Please help Gmat prep 2 PS: a certain car averages..
Replies: 11
Views: 6566

What is the OA for the above question? Thanks

by Thouraya

Thu Sep 15, 2011 10:46 pm
Forum: Data Sufficiency
Topic: Sum of consecutive integers
Replies: 7
Views: 1112

Hi Guys, I am still stuck on this problem. Is it 700-Level ? I am not quite sure how it differs from the regular work/rate problems (in that they don't mention how much each machine can perform on its own? so I can consider that they are approaching the problem the other way around?). Would apprecia...

by Thouraya

Thu Sep 15, 2011 10:30 pm
Forum: Problem Solving
Topic: Six machines each working at same constant rate together can
Replies: 23
Views: 18198

Hi @GMATguruNY,

I am still finding it challenging to determine when we would have only ONE combination of x and y that sum up to a specific total, vs when we could have more than 1 combination of values for x and y that would sum up to a certain total. Is there any way I could know? Thanks so much

by Thouraya

Thu Sep 08, 2011 11:57 pm
Forum: Data Sufficiency
Topic: gmat prep question
Replies: 18
Views: 8176

Hi,

I don't understand this problem; is it considered a difficult one or might come across it in a 650 level?

Why can't we deal with it as a regular rate/work problem? Then in 1 hour, Jack can do 1/20 and Tom 1/25..I don't know how to proceed though. I would grealy appreciate any help

by Thouraya

Thu Sep 08, 2011 4:08 am
Forum: Problem Solving
Topic: Need help
Replies: 10
Views: 2628

Improving on the Verbal

Dear @gmatguruNY, Your tips and tricks are exceptional, so I was wondering if you have any advice to offer on how to improve on the verbal section. I usually score in the high 60's percentile, but would love to score higher to help my overall grade. I would like to improve on the SC and CR; the RC I...

by Thouraya

Wed Sep 07, 2011 11:13 pm
Forum: GMAT Verbal & Essays
Topic: Improving on the Verbal
Replies: 0
Views: 1307

And is it true that the more I take the exam, the harder it gets? Thanks Geva!

by Thouraya

Mon Jul 04, 2011 10:57 pm
Forum: I just Beat The GMAT!
Topic: How to Calculate Score
Replies: 3
Views: 1756

How to Calculate Score

Hi,

If I got a 72% on Math (45), what percent shall I get on English so that I score 650 overall?

Thanks!

by Thouraya

Mon Jul 04, 2011 10:26 pm
Forum: I just Beat The GMAT!
Topic: How to Calculate Score
Replies: 3
Views: 1756

Hi @Stuart,

We have these expressions: x+y,x+5y,x-y and 5x-y

Why can't we choose either (x+y) and (x-y) OR (x+5y) and (x-y)? Why is the second option wrong to consider? Thank you!

by Thouraya

Wed Jun 29, 2011 1:08 am
Forum: Problem Solving
Topic: GMAT expressions
Replies: 9
Views: 6646

Sentence Correction

Hi, I have a few questions regarding sentence correction rules, and would appreciate an expert's help: 1) when do we use due to? vs. when do we use because? 2)when do we use "using"? vs. when do we use "based on"? 3) How come it is correct to say: "..like the planets, the st...

by Thouraya

Sun Jun 19, 2011 11:33 am
Forum: Sentence Correction
Topic: Sentence Correction
Replies: 2
Views: 1036

Can an Expert please explain this problem? Thanks

by Thouraya

Tue May 31, 2011 8:17 am
Forum: Problem Solving
Topic: A certain business produced x rakes each month form November
Replies: 9
Views: 8773