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Manhattan is an absolute must. It’ll help you build fundamentals and that’s all that you really need. Of course, start off with OG (official guide). Then, go over the Manhattan fundamentals and then practice SC qs. After a week or so, go over the Manhattan guide again before you revisit the done qs and other new qs. Do not forget to maintain an error log and keep track of the rules you discover as you practice. When you go through the OG, go through the explanation for all qs, including the ones you got right, you are likely to discover more rules than learned already. Besides, it helps you understand things GMATically. Remember, GMAT is all about rules and application of rules. So, it is a must to get tuned to the GMAT thinking styles to score well on the test.

PS: I am no expert but I assure you that I have spoken the above on behalf of top scorers.

All the very best!

Everyone has concurred on the verbal question’s answer.

here’s my approach to the quant question :

Add up all the equations. You have sum of the squares of a, b and c AND 2(b+2c+3a) = -14. What you can conclude from this equation is : a^{2, b}2 and c^2 are integers (from the given ansa choices) and their sum is even because -14 is even and 2(b+2c+3a) will be even. E+E=E

From the answer choices, only two possibilities arise – 14 / 28.

If I try to fit in 14, 2(b+2c+3a) = -42. If I substitute the expression with b= -1, c= -2 and a = -3, the equation is satisfied and eureka! I have my answer.

Cheers,

Well, I have read about Japan working on a technology that will enable certain video games to produce smell in sync with the visuals.

Stupendous! can’t express how inspiring this article is. I thank sanju09 very much for posting it. I recommend it to everyone on learnhub and outside of it. It can change your life for better forever.

big congratulations! 750 is a very respectable score. You are a VEry bright spark. Appreciate your guidance and sharing the gmat experience. I’m certain members of this community will benefit from your tips and advice. Three cheers for you!

The two formulae are applicable depending upon solution asked for and are mutually exclusive. That is, the formula in my previous post in this thread is one that gives nonnegative integral solution. The formula you have additionally mentioned, Suresh, (thanks, that would be handy) is the one that gives positive integral solutions, excluding zero value, that is.

cheers,

Indeed, there is a formula, if you like. Theese kind of questions are dealt with in the topic – distribution and grouping of like items / objects. The standard formula is C(n+r-1, r-1) where n = no of goods being distributed and r = no. of recipients.

Here’s how you must work out such questions – because the first step involves putting numbers in a figure format, which doesn’t take longer than a few seconds, I am going to ask for your help with envisioning what I have to say. There are 4 coins which can be represented by 4 tiny circles. These 4 can go into 5 recipients (to boys, that is) So, draw 4 straight lines to represent the four walls of partition next to each circle to make 5 recieving compartments / boxes. The four walls are the partitions. The space next to the last wall will have no circle representing the ‘zero coin’ possibility. So, the total no. of ways of arranging the partitions and objects (no. of coins going to one / more than one boy) is (84!) One of the 4! is for identical coins and the other is for the identical partitions.

Cheers,

I’ll start with the second first (it’s simpler :-)) -

Ramya can do a piece of work in 30 days means – she completes (1/30) part of that work in one day. In five days, she’d have completed 5(1/30) part of the work, which is simply (1/6) part of the work. Now, (5/6) part of work is left to be done by both Ramya and Shubha. shubha can complete (1/20) of the same work in one day.

So, you have Ramya contributing (1/30) and Shubha contributing (1/20) each day until 5/6 work is completed. let the number of days in which the two working together will complete the remaining 5/6 job be ‘n’. The equation is now – (1/30)n + (1/20)n = 5/6. Solving for n, you get – 10 days.

Alternately, you could write the above equation as n [(1/30) + (1/20)] = 5/6

===================================================

Solution I is as follows -

Standard practice – amount of work can be taken as 1 unit = 1. Amount of work done = productivity

In the given case, let the amount of work done by each man each day be ‘m’ and the amount of work done by each woman each day be ‘w’.

You have two variables – m and n, and two equations. Once you have the individual values, just plug in to find the answer to your question.

It is given that - 12m + 8w = (1/16) and also, 13m + 4w = (1/18).

Solving for m,n, you get m= 1/288 and n = 1/384. Now, the no. of days 13 men and 12 women will take is the reciprocal of - 13(1/288) + 12(1/384) = 11/144. That makes it 13 and 1/11 days.

Cheers,

six months past the acknowledment of the pointed out error, the error persists. I realize, patience is a virtue but…

well, saying that the day was hot is already stated and a conclusion must say something that’s not directly stated in the given context. what do ya say…

skimming, per se, is what babceo has defined. however, the question is – what is skimming used for? that could include, among other things, within the limited context of gmat, searching for information. so, while skimming is not the same as searching for information, it can be used for searching info.

I got it right but wanted this point to be considered.

As oLahav has already answered, but for the above comment, I will repeat as -

factorise the numerator, and it will be down to this expression >>>

(6x-2)(x+2).

To simplify further so as to get rid of the denominator, you can easily spot that (6x-2) is 2(3x-1) = 2 times the denominator.

so, you are left with 2(x+2) which equals 2x + 4.

cheers

Statement 2.The ratio of 2m to 3n is greater than 2.

This translates to expression :

(2m/3n) > 2 simplifying, m/n>3

and that answers the question whether m/n > 3

this is from OG :)

I somehow feel this is incorrect English. ‘according to’ should be followed by a fact / event that has either happened already or should have happened (but not in the sense of being done or initiated as in this case).

another usage is to express an opinion or view, in which case we say- according to the professor, the best time to get started… but it would be incorrect to say – according to the suggestion of the professor.

kinda tricky…isn’t it interesting that every non-prime factor is eventually a product of prime factors.

I won’t be able to give an explanation but here’s the clue – the original sentence is twisted and wordy. The part following ‘hardly be said’ needs to be fixed ‘cos it should have been something like – to be their fault – to make sense. You may also compare the original sentence with the corrected one – C – and you will have the answer to ‘why’.

though, accordign to the dictionary, it is a multi-level parking structure

or, you could also solve for the answer using weighted averages.

Since profit equals sales price – cost price, profit in this case using weighted averages will be -

{(3/4) X (1/2) + (1/4) X (1/5)} X 6000.

3/4 represents 75% of the claculators, 1/2 is the profit on this 75% (it is given that they were sold for 50% above cost price), 1/4 for the remaining 25% calculators and 1/5 is the 20% profit on these.

Just as we use the set theories in probability questions, it is not a bad idea to use weighted averages in such questions as the one here. saves time and work. ‘Course, you are free to discard it and continue using methods that you are comfortable using :)

Though mohit has already done the work -

from the equation already given (I am omitting the basic calculation steps of cross multiplying the denominator and numerator on either isde of the equation), it follows that (x^{2) + 3x -12 = 0}

the question is – what is (x2) + 3x -2? Comparing the simplied form of the given equation with the question, you can solve for the answer = 10. As you can see, the two equations have (x^2) and 3x terms in common, the only difference is in the constant’s value. You don’t have to find the roots of x to know the answer, I think, that’s the trap here.

cheers,