Search found 58 matches
If the distance from castle to the moat is r, then the total length of all the pathways = (length of the circular pathway) + (length of the square pathway) + (length of the four straight pathways from the castle to the moat) = (2*pi*r) + 4*(root(2)*r) + 4*r = q Solve for 'r' from this equation and y...
- by gmat_and_me
Fri Jun 22, 2012 10:25 pm- Forum: Problem Solving
- Topic: manhattan cat geometry question help me.
- Replies: 6
- Views: 2453
Probability is not the problem. Counting is the problem that most people find tough. Internet is a vast resource. Start looking at simple resources that explain what permutation and combination are. Then solve simple problems and get your basics right. Once you are comfortable, you can graduate to t...
- by gmat_and_me
Fri Jun 22, 2012 5:09 am- Forum: Problem Solving
- Topic: how to undersatand probability
- Replies: 3
- Views: 1373
ARC BF = 1/6-th => BAF = 60 degree => BAF is an equilateral triangle. => radius of the circle = 2 Now area of the shaded portion = Area of triangle ACE - Area of sector AFEA Area of triangle ACE = 1/2 * base * height = 1/2 * 2 * 2 (since AE = 2 and AB = 2) = 2 Area of sector AFEA = 1/12-th of area o...
- by gmat_and_me
Fri Jun 22, 2012 4:56 am- Forum: Problem Solving
- Topic: Area of shaded region
- Replies: 2
- Views: 2055
If you have posted the question right, then D is the answer. In
general, if you break down a number into it's prime factors,
X = (p)^a * (p1)^b * ...
then the number of different factors will be (a+1) * (b+1) *...
and so on...
HTH
- by gmat_and_me
Fri Jun 22, 2012 4:33 am- Forum: Problem Solving
- Topic: Help needed
- Replies: 4
- Views: 2381
Given the 5 choices in the exam, I will pick C. Having said that, C changes the meaning of the sentence (as per me), and I can not agree with Karthik's explanation. If we are talking about last century and current century, last century is past and hence the construction, I feel, is wrong. "stat...
- by gmat_and_me
Tue Jun 19, 2012 7:30 am- Forum: Sentence Correction
- Topic: Despite the recent election of a woman
- Replies: 8
- Views: 3355
This approach doesn't seem correct. First of all this is a problem without replacement. That means that every time you pick a ball, the denominator for calculation of probability has to decrease by 1. So, _as per your method_, the probability will have to be 2/8 * 3/7 * 2/6 * 3/5 * 2/4 = 3/280 (in t...
- by gmat_and_me
Tue Jun 19, 2012 7:15 am- Forum: Problem Solving
- Topic: Probability question
- Replies: 12
- Views: 3428
Is the the answer C ? Originally the company would have had 122 * 122 codes. With the addition of the two new codes, the total will be 124 * 124. So, additional codes will be 122 * 2 + 2 * 124 (if you want to look at the problem without doing complex calculation). HTH The telephone company wants to ...
- by gmat_and_me
Tue Jun 19, 2012 4:55 am- Forum: Problem Solving
- Topic: Permutation
- Replies: 10
- Views: 1793
Hello KapTeacherEli, For some reason the poster of the question changed the complete question. My responses were for the questions mentioned in http://www.beatthegmat.com/weak-on-geometry-t114255.html If you know the sources and the complete question for the above thread, please do give further insi...
- by gmat_and_me
Mon Jun 18, 2012 7:02 pm- Forum: Problem Solving
- Topic: Airthmetic
- Replies: 8
- Views: 1725
I think option C should ideally be "has changed little from how it was".
D is not definitely not right. You should probably not rack your brains
about this question.
HTH
- by gmat_and_me
Mon Jun 18, 2012 5:27 am- Forum: Sentence Correction
- Topic: Despite the recent election of a woman
- Replies: 8
- Views: 3355
Statement 1 alone should be sufficient here, if I'm right. ABC similar to XYC similar to RSC. Since they are similar, area of RSC should be 1/16-th of area of ABC (how ? For triangle XYC, XY = 1/2 AB (similar triangles, CX = 1/2 AC, CY = 1/2 BC). Similarly, height of XYC = 1/2 height of ABC. So area...
- by gmat_and_me
Sat Jun 16, 2012 10:30 pm- Forum: Data Sufficiency
- Topic: OG 12190 DS
- Replies: 2
- Views: 1054
Nearest mile, as I understand, is 0.5 < X < 1.5 because anything slightly above .5 is nearer to 1 than to 0 and anything infinitesimally less than 1.5 is nearer to 1. For example anything between 224.50000....1 to 225.499......9 should be 225. You can approximate this range to be between 224.5 and 2...
- by gmat_and_me
Sat Jun 16, 2012 10:06 pm- Forum: Problem Solving
- Topic: "Rounded to the nearest" - What does that term mea
- Replies: 2
- Views: 12944
There are actually 6 people. If you see my first post, you can ignore the condition that one person in absent, since empty chair in one of the places is also an arrangement. For eg: Alex Empty_Chair 3 4 5 6 is different from Empty_Chair Alex 3 4 5 6 right ? HTH Let's take one instance of this arrang...
- by gmat_and_me
Sat Jun 16, 2012 6:52 pm- Forum: Problem Solving
- Topic: Probability Question ..Need expert help
- Replies: 18
- Views: 3414
Your first solution is very nice. I can not make sense of 2 and 3. 4 you are part right. The mistake that you made in 4 is that you used combination in denominator while you did not use combination in numerator. Look at it this way. First card you can select from any of the 52 cards. But the second ...
- by gmat_and_me
Fri Jun 15, 2012 7:31 am- Forum: Problem Solving
- Topic: Probability MGMAT
- Replies: 15
- Views: 4254
Sum of the roots of the equation ax^2 + bx + c = 0
is -b/a
Product of the roots = c/a
roots of such an equation are
(-b + rootof(b^2 - 4ac)) / 2a
and
(-b - rootof(b^2 - 4ac)) / 2a
HTH
- by gmat_and_me
Fri Jun 15, 2012 5:55 am- Forum: Problem Solving
- Topic: 300 tough Algebra
- Replies: 20
- Views: 39581
I do not think that these problems are solvable with the data provided. Unfortunately these problems does not provide any answers. If you would like to help me it is up to you. It is a complete problem. Thanks. Huh ? It is up to me ? Yeah, really not needed OK. Will you mind posting the complete pro...
- by gmat_and_me
Fri Jun 15, 2012 5:46 am- Forum: Problem Solving
- Topic: Airthmetic
- Replies: 8
- Views: 1725