Search found 44 matches
FREE GMAT Math Online Office Hours - 11/07/09
Hi everyone, I'm an instructor at www.GMATPrepMath.com. We are hosting FREE weekly online office hours to go through GMAT math questions that you are having trouble with. You may submit up to two problems. We will select 5-6 problems from the submissions to work on during class. You should take adva...
- by GMATQuantCoach
Thu Nov 05, 2009 1:30 pm- Forum: Lounge
- Topic: FREE GMAT Math Online Office Hours - 11/07/09
- Replies: 0
- Views: 2123
FREE Online GMAT Math Session - 10/24/09
Hi everyone, I am an instructor at www.GMATPrepMath.com. We are hosting a FREE online session on the topic “Banking Time with Faster Calculations�. This class is designed to lay grounds for the various types of calculations that you will be performing on GMAT. You will learn time-saving techniqu...
- by GMATQuantCoach
Tue Oct 13, 2009 10:13 am- Forum: Lounge
- Topic: FREE Online GMAT Math Session - 10/24/09
- Replies: 0
- Views: 1605
2) Consider two cases: x>=0 and x<0. If x>=0, then y = |x| + x = x + x = 2x. That implies y >=0 because x>=0. y is an integer such that 0 <= y < 1. y can only be 0. If x < 0, then y = |x| + x = -x + x = 0. In both cases y = 0. That means no matter what x values you pick, y is equal to 0. Sufficient.
- by GMATQuantCoach
Sat Sep 19, 2009 3:58 pm- Forum: Data Sufficiency
- Topic: Inequalities
- Replies: 7
- Views: 1591
Connect AD and BD.
Triangle ADB must be a right triangle.
We can show that triangle ACD is similar to triangle DCB. Then
AC/CD = CD/CB
CD^2 = AC * CB
36 = 2 * CB
CB = 18
Radius = (AC + CB)/2 = 10
Area of Semi-Circle = 1/2 * pi * r^2 = 50pi
B is the answer.
- by GMATQuantCoach
Sat Sep 19, 2009 3:47 pm- Forum: Problem Solving
- Topic: Tough Geom2
- Replies: 4
- Views: 2226
First, make sure that the fraction is in its simplest form.
The denominator of a terminating decimal must only contain factors of 2's or 5's.
- by GMATQuantCoach
Sun Aug 09, 2009 4:52 pm- Forum: GMAT Math
- Topic: Terminating decimals
- Replies: 3
- Views: 1956
Re: combination
If x, y, and z are positive integers, and x + y + z = 9. How many combinations of x, y, and z are possible? OA 28 I won't require you to attend a seminar before providing the solution. Who is that guy/girl and who let him/her into our fine community? Heh. Let's think about the different ways we can...
- by GMATQuantCoach
Wed Jul 22, 2009 7:32 pm- Forum: Problem Solving
- Topic: combination
- Replies: 13
- Views: 3915
If you like see the approach, please join my upcoming combinatorics session.
You will get to work on a lot more of these questions in my session and in the additional homework that I will be giving out.
- by GMATQuantCoach
Wed Jul 22, 2009 4:05 pm- Forum: Problem Solving
- Topic: combination
- Replies: 13
- Views: 3915
If you break all numbers from 1 to 7 into prime factors, you get. 1 = 1^1 2 = 2^1 3 = 3^1 4 = 2^2 5 = 5^1 6 = 2^1 * 3^1 7 = 7^1 So the minimal prime factors that the least positive integer must have is 1^1 * 2^2 * 3^1* 5^1 *7^1 = 1*4*3*5*7 = 420. If on the test, you can start checking the answers fr...
- by GMATQuantCoach
Tue Jul 21, 2009 10:36 am- Forum: Problem Solving
- Topic: least positive
- Replies: 5
- Views: 1307
moonshine,
I have created one. You can find it from www.GMATMathSheet.com. The ebook version of it is just $10.
- by GMATQuantCoach
Tue Jul 21, 2009 9:52 am- Forum: GMAT Math
- Topic: Formulae Sheet and speed math
- Replies: 6
- Views: 2810
It was my pleasure to conduct the free session. I hope for those who attended, you enjoyed the session and actually learned something useful from the session. Feel free to leave me feedback so that I can improve my future sessions. For next week, I am hosting a 2-hour online session on combinatorics...
- by GMATQuantCoach
Mon Jul 20, 2009 10:49 am- Forum: Lounge
- Topic: FREE Live Online GMAT Math Session
- Replies: 11
- Views: 4738
I will use _ to represent subscript. a_n = (n+2)/n a_n * a_(n+2) = (n+2)/n * (n+4)/(n+2) = (n+4)/n a_n * a_(n+2) * a_(n+4) = (n+4)/n * (n+6)/(n+4) = (n+6)/n . . . a_n * a_(n+2) * a_(n+4) * ... * a_(n+8) = (n+10)/n Then let n = 1 a_1 * a_3 * ...* a_7 * a_9 = (1 + 10)/1 = 11 Let n = 2 a_2 * a_4 * ... ...
- by GMATQuantCoach
Mon Jul 13, 2009 4:13 pm- Forum: Problem Solving
- Topic: Tough Sequence Question
- Replies: 3
- Views: 1560
1. 1/(k-1) > 0
Then k - 1 > 0
k >1
Then 1/k > 0.
Sufficient.
2. 1/(k+1)>0
k+1>0
k>-1
Choose k = -1/2, then 1/k = -2.
Choose k = 1/2, then 1/k = 2.
Insufficient.
Answer is A.
- by GMATQuantCoach
Mon Jul 13, 2009 3:55 pm- Forum: Data Sufficiency
- Topic: gmatprep k does not = -1,0,1, is (1/k) > 0?
- Replies: 6
- Views: 1532
FREE Live Online GMAT Math Session
FREE Live Online GMAT Math Session To share my GMAT math expertise with the community, I am hosting a FREE live online session on the topic “Banking Time with Faster Calculations”. The goal of this session is to bank time and to minimize careless mistakes by boosting calculation speed and accuracy....
- by GMATQuantCoach
Mon Jul 13, 2009 10:21 am- Forum: Lounge
- Topic: FREE Live Online GMAT Math Session
- Replies: 11
- Views: 4738
(1) 2x-2y=1 2(x - y) = 1 x - y = 1/2 x = 1/2 + y choose y = 1, then x = 3/2 choose y = -1, then x = -1/2 Insufficient (2) x/y > 1 x/y - 1 > 0 (x-y)/y > 0 choose x = 2, y = 1 choose x = -2, y = -1 Insufficient. When combined. x - y = 1/2 (x-y)/y > 0 Replace x - y with 1/2 1/(2y) > 0 Then y >0 x = 1/2...
- by GMATQuantCoach
Sun Jul 12, 2009 3:52 pm- Forum: Data Sufficiency
- Topic: x and y
- Replies: 1
- Views: 1243
You will need to know how to add inequalities to isolate variables like you do when solving simultaneous linear equations. x + y + z > 0 then z > - x - y (Let's call it inequality [1]) (1) z > x + y +1 (let's call it inequality [2]) Add inequality [1] with inequality [2] yields 2z > 1 z > 1/2 You ca...
- by GMATQuantCoach
Sat Jul 11, 2009 2:11 pm- Forum: Data Sufficiency
- Topic: If x + y + z > 0, is z > 1?
- Replies: 4
- Views: 5460