Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized for You

we will pick new questions that match your level based on your Timer History

Track Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

It appears that you are browsing the GMAT Club forum unregistered!

Signing up is free, quick, and confidential.
Join other 500,000 members and get the full benefits of GMAT Club

Registration gives you:

Tests

Take 11 tests and quizzes from GMAT Club and leading GMAT prep companies such as Manhattan GMAT,
Knewton, and others. All are free for GMAT Club members.

Applicant Stats

View detailed applicant stats such as GPA, GMAT score, work experience, location, application
status, and more

Books/Downloads

Download thousands of study notes,
question collections, GMAT Club’s
Grammar and Math books.
All are free!

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

==> In the original condition, there are 2 variables (x, y) and in order to match the number of variables to the number of equations, there must be 2 equations. Since there is 1 for con 1) and 1 for con 2), C is most likely to be the answer. By solving con 1) and con 2), you get (x,y)=(1,3),(3,1),(-1,-3),(-3,-1), and all become \((x-y)^2=4\), hence it is unique and sufficient.

Therefore, the answer is C. Answer: C
_________________

What is the scope including 1/11+1/12+1/13+......+1/20?

A 1/6~1/5 B. 1/5~1/4 C. 1/4~1/3 D. 1/3~1/2 E. 1/2~1

The sum of consecutive reciprocal number sequence is decided by the first number and the last number. Thus, from 10/20=1/11+1/12+.....+1/20<1/11+1/12+.....+1/20<1/11+1/12+.....+1/20=10/11, you get 1/2=10/20<1/11+1/12+.....+1/20<10/11<1, which becomes 1/2~1.

Therefore, the answer is E. Answer: E
_________________

==> If you modify the original condition and the question, \((x+y)^2-(x-y)^2=?\) becomes (x+y-x+y)(x+y+x-y)=?, and if you simplify this, you get (2y)(2x)=?, 4xy=?. Thus, for con 1), you get xy=5, hence it is unique and sufficient. The answer is A. Answer: A
_________________

==> In the original condition, there are 2 variables (a,b) and in order to match the number of variables to the number of equations, there must be 2 equations. Since there is 1 for con 1) and 1 for con 2), C is most likely to be the answer. By solving con 1) and con 2), from a=2, you get b2=22=4, then b=±2. Thus, (a,b)=(2,2) yes but (a,b)=(2,-2) no, hence it is not sufficient. The answer is E. Answer: E
_________________

What is the perimeter of a certain right triangle?

1) The hypotenuse’s length is 10 2) The triangle’s area is 24

==> In the original condition, for a right triangle, there are 2 variables (2 legs) and in order to match the number of variables to the number of equations, there must be 2 equations. Since there is 1 for con 1) and 1 for con 2), C is most likely to be the answer. By solving con 1) and con 2), you get 6:8:10 and the perimeter of the right triangle becomes 6+8+10=24, hence unique and sufficient.

Therefore, the answer is C. Answer: C
_________________

==> You can compare the big and small numbers by making the base or the exponent the same. From\(A=6^2^0, B=2^6^0=(2^3)^2^0=8^2^0\), you get 6<8, which becomes A<B, and from \(B=2^6^0=(2^2)^3^0=4^3^0, C=4^5^0,\) you get 30<50, which becomes B<C.

Thus, you get A<B<C. The answer is A. Answer: A
_________________

In the x-y plane, what is the slope between y-intercept and a negative x-intercept of \(y=x^2+x-6\)?

A. -2 B. -3 C. 2 D. 4 E. 6

==> From y=x2+x-6=(x+3)(x-2)=0, the x-intercept becomes (-3,0) or (2,0), and (0,-6). From these, the negative x-intercept is (-3,0) and the negative y-intercept is (0,-6). The slope of the straight line that passes through the two points becomes \(\frac{0-(-6)}{-3-0=-2}\)

Is a positive integer n a multiple of 12 1) n is a multiple of 6 2) n is a multiple of 24

==> In the original condition, there is 1 variable (n) and in order to match the number of variables to the number of equations, there must be 1 equation. Since there is 1 for con 1) and 1 for con 2), D is most likely to be the answer. For remainder questions, you always use direct substitution. For con 1), n=6 no, n=12 yes, hence not sufficient. For con 2), n=24,48,…, hence it is always yes and sufficient.

Therefore, the answer is B. Answer: B
_________________

==> In the original condition, there are 3 variables (x,y,z) and in order to match the number of variables to the number of equations, there must be 3 equations. Since there is 1 for con 1) and 1 for con 2), E is most likely to be the answer. By solving con 1) and con 2), from x>y>z, it is always yes and sufficient.

Therefore, the answer is C. Answer: C
_________________

Is a positive integer x a factor of 24? 1) 3x is a factor of 48 2) 2x is a factor of 24

==> In the original condition, there is 1 variable (x) and in order to match the number of variables to the number of equations, there must be 1 equation. Since there is 1 for con 1) and 1 for con 2), D is most likely to be the answer. For con 1), x is a factor of 16, so x=8 yes, x=16 no, hence not sufficient. For con 2), x is a factor of 12, so it is always yes, hence sufficient.

Therefore, the answer is B. Answer: B
_________________

In the x-y plane there is a line K, (x/a)+(y/b)=1. What is the x-intercept of line K?

1) a=b 2) a=1

==> If you modify the original condition and the question, the x-intercept is the value of x when y=0, hence from (x/a)=1, you get x=a, so you only need to find a.

Therefore, the answer is B. Answer: B
_________________

==> In the original condition, there is 1 variable (m) and in order to match the number of variables to the number of equations, there must be 1 equation. Since there is 1 for con 1) and 1 for con 2), D is most likely to be the answer. For con 1), from m=5,10…, it is not unique and not sufficient. For con 2), from m=5,7…, it is not unique and not sufficient. By solving con 1) and con 2), you get m=5, hence it is unique and sufficient.

Therefore, the answer is C. Answer: C
_________________

If two times x is 5 greater than three times y, what is the value of y, in terms of x?

A. y=2x-5 B. y=6x-5 C. y=(x/2)-5 D. y=(x/3)-5 E. y=(2x-5)/3

==> According to the Ivy Approach, you get is:”=” and greater than:”+”, so you get 2x=5+3y. From 3y=2x-5, y=(2x-5)/3, the answer is E. Answer: E
_________________

==> In the original condition, there are 2 variables (x,y) and in order to match the number of variables to the number of equations, there must be 2 equations. Since there is 1 for con 1) and 1 for con 2), C is most likely to be the answer. By solving con 1) and con 2), from x<√x, you get 0<x<1, and from √y<y, you get y>1. Then, you get x<1<y, hence always yes.

[m] is defined as the greatest integer less than or equal to m, what is the value of [m]?

1) 1<m<2 2) |m|<1

==> In the original condition, there is 1 variable (m) and in order to match the number of variables to the number of equations, there must be 1 equation. Since there is 1 for con 1) and 1 for con 2), D is most likely to be the answer. For con 1), from [m]=1, it is unique and sufficient. For con 2), from -1<m<1, you get [0]=0, but from [0.1]=-1, it is not unique and not sufficient.

Therefore, the answer is A. Answer: A
_________________

If 1 male, 2 females, and 1 child are to be selected at random from 8 males, 10 females, and 8 children, respectively, how many such cases are possible?

A. 980 B. 1,440 C. 1,880 D. 2,480 E. 2,880

==> From (8C1)(10C2)(8C1)=(8)(10*9/2!)(8)=2,880, the answer is E. Answer: E
_________________