Search found 80 matches
If /M+4/=2, what is the value of M? /module/ (1) M<0 (2) M^2+8M+12=0 The stimulus can be solved for M = -2 or M = -6 (1) does not clarify if it's M = -2 or M = -6 since both are negative. (2) M^2+8M+12=0 can be factored into: (M+2)(M+6) = 0, which also has the two solutions M = -2 and M = -6. Even w...
- by grockit_jake
Fri Nov 13, 2009 2:21 pm- Forum: Data Sufficiency
- Topic: value M
- Replies: 2
- Views: 1148
The angles are also in the same relative order as their opposite sides.
In any triangle ABC,
AB + BC > CA
AC + AB > CB
AC + CB > AB
- by grockit_jake
Fri Nov 13, 2009 2:18 pm- Forum: GMAT Math
- Topic: 3rd side of a triangle
- Replies: 3
- Views: 1668
Note you are not looking for n. You are looking for the largest positive integer that must divide n. The smallest n = 12, so n^2 = 144, like you said. 144 is divisible by every answer choice. Since (e) is the greatest.... Note that 12 = 2*2*3, so 12^2 = 2*2*2*2*3*3. 72 = 6*6*2 = 3*3*2*2*2. You MUST ...
- by grockit_jake
Tue Nov 10, 2009 12:15 pm- Forum: Problem Solving
- Topic: Number Properties
- Replies: 6
- Views: 1876
An expression is 1 side of an equation. so:
4*sqrt(16) + 6 = x
would convert to
4*4 + 6 = x
NOT
4* (+/-4) + 6 = x
for query 2, the answer is the same. when you take the square root of a number in an expression, you dont consider the -
- by grockit_jake
Tue Nov 10, 2009 10:32 am- Forum: Problem Solving
- Topic: Please explain
- Replies: 4
- Views: 1388
For some reason, mathematicians made a decision on this back in the 1400s. When you have a square root of a number that is not in an equation, then you only take the positive root. For example: sqrt(9) equals 3 only 9 = x^2 x = +/- 3 The distinction is if you are solving an EQUATION for distinct roo...
- by grockit_jake
Tue Nov 10, 2009 10:19 am- Forum: Problem Solving
- Topic: Please explain
- Replies: 4
- Views: 1388
Absolute value equations yield 2 solutions, just like quadratic equations |x+2| = 4 means x = 2 or x = -6. (1) says x does NOT equal 2 or -2. x =-6 by default. Sufficient. (2) says x = +/- 6. x = -6 then. Sufficient. Note that if you end up with different answers from (1) and (2), then something wen...
- by grockit_jake
Tue Nov 10, 2009 10:10 am- Forum: Data Sufficiency
- Topic: |x+2|
- Replies: 3
- Views: 1534
Did it come from this article?
http://www.beatthegmat.com/a/2009/11/02/inequalities
There is a detailed explanation here.
- by grockit_jake
Tue Nov 10, 2009 9:27 am- Forum: Problem Solving
- Topic: PS - absolute value / number line
- Replies: 5
- Views: 1222
Since each report is assigned randomly, you can look at each report as its own probability: Since there are 3 options of where each report can do and 4 total reports, your total number of options is 3*3*3*3 = 3^4. I would look at the term "at least 1" as "NOT Zero" or "1 - Z...
- by grockit_jake
Fri Nov 06, 2009 12:00 pm- Forum: Problem Solving
- Topic: Tough probability
- Replies: 28
- Views: 9612
We know that there are 20 total trucks, so the number at the lot on Saturday is (1/2 the amount rented) + (20 - amount rented). Algebraically it's: 1/2R + (20 - R) >= 12 -1/2R + 20 >= 12 1/2R <= 8 R <= 16 Or, you can look for the pattern with the answer choices: 10 rented : 5 + 10 = 15 12 rented : 6...
- by grockit_jake
Fri Nov 06, 2009 11:29 am- Forum: Problem Solving
- Topic: Trucks
- Replies: 7
- Views: 4341
A quick way to think about most geometry question is to access 2 things: angles and lengths. If the question asks for exact length, then you must be provided with some baseline length. Statement 1 is obviously not sufficient since it doesn't provide length. Statement 2 doesn't provide enough about t...
- by grockit_jake
Wed Nov 04, 2009 1:42 pm- Forum: Data Sufficiency
- Topic: Triangles
- Replies: 8
- Views: 1683
- by grockit_jake
Wed Nov 04, 2009 1:36 pm- Forum: Problem Solving
- Topic: Triangles
- Replies: 2
- Views: 979
any two lines that are not parallel intersect at one place. There are 2 strategies to go from 2 variables (x and y) to 1 variable. Once you solve for one of the variables, you can then plug into either equation and solve for the other. y = 5x - 3 y = -4x + 6 1) Subtract equations: y - y = (5x - 3) -...
- by grockit_jake
Wed Nov 04, 2009 1:34 pm- Forum: Problem Solving
- Topic: Coordinate Geometry
- Replies: 2
- Views: 1201
Given that they intersect at a point (5,1) in this case, the other point is important in determining the slope. If one line always hits the y-axis higher than the other, then that means 1. their slopes are different 2. If the slopes are positive, the slope of the line hitting highest on the y-axis (...
- by grockit_jake
Thu Oct 29, 2009 3:43 pm- Forum: Data Sufficiency
- Topic: Slope
- Replies: 4
- Views: 2409
There seems to be something wrong with A.
a. 7 < x > 11
This says x is greater than 7 and greater than 11, which is repetitive.
- by grockit_jake
Thu Oct 29, 2009 8:55 am- Forum: Data Sufficiency
- Topic: Median
- Replies: 2
- Views: 1334
The difference between C and D is that D says II will decrease. II. -10 - 1/(x^2) The -10 is a constant so don't worry about that. Let's take it one step at a time. When x increases, x^2 increases. Since x^2 is in the denominator, the entire term 1/(x^2) DECREASES. Since that entire term is being su...
- by grockit_jake
Thu Oct 29, 2009 8:53 am- Forum: Problem Solving
- Topic: which must decrease
- Replies: 1
- Views: 1578