All GRE Math Resources
Example Questions
Example Question #1 : How To Find The Radius Of A Sphere
If a sphere has a volume of cubic inches, what is the approximate radius of the sphere?
The formula for the volume of a sphere is
where is the radius of the sphere.
Therefore,
, giving us .
Example Question #2 : How To Find The Radius Of A Sphere
A rectangular prism has the dimensions . What is the volume of the largest possible sphere that could fit within this solid?
For a sphere to fit into the rectangular prism, its dimensions are constrained by the prism's smallest side, which forms its diameter. Therefore, the largest sphere will have a diameter of , and a radius of .
The volume of a sphere is given as:
And thus the volume of the largest possible sphere to fit into this prism is
Example Question #1541 : Gre Quantitative Reasoning
What is the radius of a sphere with volume cubed units?
The volume of a sphere is represented by the equation . Set this equation equal to the volume given and solve for r:
Therefore, the radius of the sphere is 3.
Example Question #1 : Exponential Operations
Simplify
None
Divide the coefficients and subtract the exponents.
Example Question #472 : Algebra
Which of the following is equal to the expression , where
xyz ≠ 0?
xyz
z
z/(xy)
1/y
xy
1/y
(xy)4 can be rewritten as x4y4 and z0 = 1 because a number to the zero power equals 1. After simplifying, you get 1/y.
Example Question #473 : Algebra
If , then
Cannot be determined
Start by simplifying the numerator and denominator separately. In the numerator, (c3)2 is equal to c6. In the denominator, c2 * c4 equals c6 as well. Dividing the numerator by the denominator, c6/c6, gives an answer of 1, because the numerator and the denominator are the equivalent.
Example Question #1 : How To Divide Exponents
If , which of the following is equal to ?
a6
The answer cannot be determined from the above information
a18
a
a4
a18
The numerator is simplified to (by adding the exponents), then cube the result. a24/a6 can then be simplified to .
Example Question #1542 : Gre Quantitative Reasoning
[641/2 + (–8)1/3] * [43/16 – 3171/3169] =
–30
30
–5
16
9
–30
Let's look at the two parts of the multiplication separately. Remember that (–8)1/3 will be negative. Then 641/2 + (–8)1/3 = 8 – 2 = 6.
For the second part, we can cancel some exponents to make this much easier. 43/16 = 43/42 = 4. Similarly, 3171/3169 = 3171–169 = 32 = 9. So 43/16 – 3171/3169 = 4 – 9 = –5.
Together, [641/2 + (–8)1/3] * [43/16 – 3171/3169] = 6 * (–5) = –30.
Example Question #1543 : Gre Quantitative Reasoning
Evaluate:
Distribute the outside exponents first:
Divide the coefficient by subtracting the denominator exponents from the corresponding numerator exponents:
Example Question #41 : Exponents
The easiest way to solve this is to simplify the fraction as much as possible. We can do this by factoring out the greatest common factor of the numerator and the denominator. In this case, the GCF is .
Now, we can cancel out the from the numerator and denominator and continue simplifying the expression.