GRE Math : GRE Quantitative Reasoning
Study concepts, example questions & explanations for GRE Math
All GRE Math Resources
Example Questions
Example Question #4 : Combinations
Quantity A: The number of combinations if five choices are made from ten options.
Quantity B: The number of combinations if two choices are made from twenty options.
The relationship cannot be determined.
Quantity A is greater.
The two quantities are equal.
Quantity B is greater.
Quantity A is greater.
Since we're dealing with combinations in this problem, the order of selection does not matter.
With 
Quantity A:
Quantity B:
Quantity A is greater.
Example Question #24 : How To Find The Greatest Or Least Number Of Combinations
Davis is trying to decide on an ensemble. He has ten pairs of socks to choose from, six bracelets (he'll wear a different one on each wrist), and four pairs of sun glasses. How many ways can he create an outfit?
With 
With 
When choosing the socks and sunglasses, order does not matter; however, in electing bracelets, order does matter: for instance, a blue on the left and green on the right is different than a green on the left and blue on the right!
Consider the results case by case:
Socks:
Bracelets:
Sunglasses:
The number of potential ensembles is the product of these:
Example Question #83 : Probability & Statistics
Lisa is dressing warm for the winter. She'll be layering three shirts over each other, and two pairs of socks. If she has fifteen shirts to choose from, along with ten different kinds of socks, how many ways can she layer up?
Since the order in which Lisa layers up matters, we're dealing with permutations.
With 
For her shirts:
For her socks:
Her total ensemble options is the product of these two results
Example Question #331 : Arithmetic
Quantity A: The number of possible combinations when three choices are made from six options.
Quantity B: The number of possible permutations when three choices are made from four options.
The two quantities are equal.
The relationship cannot be determined.
Quantity B is greater.
Quantity A is greater.
Quantity B is greater.
With 
With 
Quantity A:
Quantity B:
Quantity B is greater.
Example Question #21 : How To Find The Greatest Or Least Number Of Combinations
Quantity A: The number of potential combinations when three choices are made from seven options.
Quantity B: The number of potential combinations when four choices are made from seven options.
The relationship cannot be determined.
Quantity A is greater.
Quantity B is greater.
The two quantities are equal.
The two quantities are equal.
With
Quantity A:
Quantity B:
It is not necessary to perform this calculation, (although the value for each is thirty-five) and on the GRE needless calculations should be avoided.
The two quantities are equal.
Example Question #1 : Permutations
Quantity A: The number of possible permutations when seven choices are made from ten options.
Quantity B: The number of possible permutations when five choices are made from eleven options.
Quantity A is greater.
The two quantities are equal.
Quantity B is greater.
The relationship cannot be determined.
Quantity A is greater.
With
Quantity A:
Quantity B:
Quantity A is greater.
Example Question #31 : Permutation / Combination
Quantity A: The number of combinations if four choices are made from eight options.
Quantity B: The number of combinations if five choices are made from eight options.
Quantity B is greater.
The two quantities are equal.
The relationship cannot be determined.
Quantity A is greater.
Quantity A is greater.
With
Quantity A:
Quantity B:
Quantity A is greater.
Example Question #342 : Arithmetic
Jack is putting together his winter ensemble to take with him on a weekend ski trip. He'll be bringing two scarves out of a selection of twelve, four pairs of socks from a group of ten, and three sweaters from a choice of six. How many clothing combinations are available to him?
Since in this problem the order of selection does not matter, we're dealing with combinations.
With 
We'll be dealing with the potential combinations for the scarves, socks, and sweaters; the total amount of combinations will be the product of these three.
Scarves:
Socks:
Sweaters:
The total number of combiations is
He's certainly not hurting for choices.
Example Question #2 : Permutations
Jill is picking out outfits for a three-day weekend, one for Friday, one for Saturday, and one for Sunday.
Fortunately all of her clothes match together really well, so she can be creative with her options, though she's decided each outfit is going to be a combination of blouse, skirt, and shoes.
She'll be picking from ten blouses, twelve skirts, and eight pairs of shoes. How many ways could her weekend ensemble be lined up?
For this problem, order matters! Wearing a particular blouse on Friday is not the same as wearing it on Sunday. So that means that this problem will be dealing with permutations.
With
What we'll do is calculate the number of permutations for her blouses, skirts, and shoes seperately (determining how the Friday/Saturday/Sunday blouses/skirts/shoes could be decided), and then multiply these values.
Blouses:
Skirts:
Shoes:
Thus the number of potential outfit assignments is
Example Question #32 : Permutation / Combination
Sammy is at an ice cream shoppe, aiming to build a sundae from two different flavors from a choice of thirty-one, and three separate toppings from a choice of ten. How many kinds of sundaes can he make?
Since in this problem the order of selection does not matter, we're dealing with combinations.
With
Sammy is making two sub combinations; one of ice cream and one of toppings. The total amount of combinations will be the product of these two.
Ice cream:
Toppings:
The total number of potential sundaes is
All GRE Math Resources
