All GRE Math Resources
Example Questions
Example Question #51 : Fractions
Car A traveled 120 miles with 5 gallons of fuel.
Car B can travel 25 miles per gallon of fuel.
Quantity A: The fuel efficiency of car A
Quantity B: The fuel efficiency of car B
Quantity A is greater.
Quantity B is greater.
The two quantities are equal.
The relationship cannot be determined.
Quantity B is greater.
Let's make the two quantities look the same.
Quantity A: 120 miles / 5 gallons = 24 miles / gallon
Quantity B: 25 miles / gallon
Quantity B is greater.
Example Question #464 : Arithmetic
Quantity A:
The -value of the equation when
Quantity B:
Both quantities are equal
Quantity B is greater.
Quantity A is greater.
The relationship cannot be determined from the information given.
Quantity A is greater.
In order to solve quantitative comparison problems, you must first deduce whether or not the problem is actually solvable. Since this consists of finding the solution to an -coordinate on a line where nothing too complicated occurs, it will be possible.
Thus, your next step is to solve the problem.
Since and , you can plug in the -value and solve for :
Plug in y:
Add 2 to both sides:
Divide by 3/4. To divide, first take the reciprocal of 3/4 (aka, flip it) to get 4/3, then multiply that by 5/3:
Make the improper fraction a mixed number:
Now that you have what x equals, you can compare it to Quantity B.
Since is bigger than 2, the answer is that Quantity A is greater
Example Question #1 : How To Divide Fractions
What is equivalent to ?
Remember that when you divide by a fraction, you multiply by the reciprocal of that fraction. Therefore, this division really is:
At this point, it is merely a matter of simplification and finishing the multiplication:
Example Question #465 : Arithmetic
Which of the following is equivalent to ?
To begin with, most students find it easy to remember that...
From this, you can apply the rule of division of fractions. That is, multiply by the reciprocal:
Therefore,
Since nothing needs to be reduced, this is your answer.
Example Question #1051 : Gre Quantitative Reasoning
Carpenter A takes 45 hours to build a table. Carpenter B takes 30 hours. When they work together, how long will it take them to build a table?
Write their respective rates as fractions:
Carpenter A:
Carpenter B:
Add them together to find their combined rate. First find a common denominator. The smallest multiple of both 45 and 30 is 90:
Therefore, they take 18 hours to build a table together.
Example Question #51 : Fractions
What is the sum of the reciprocal of , the reciprocal of , the reciprocal of , and ?
None of the other answers
Begin by finding the reciprocal of , the reciprocal of , and the reciprocal of :
, ,
In order to add the four terms together, we will need to find a common denominator. Find the common denominator by multiplying the three different terms in the denominator (x, y, and z). Our common denominator will be . Put each term into terms of this common denominator:
Now, add each term together:
Look for the answer choice that matches this.
Example Question #52 : Fractions
Find the reciprocal of the following expression:
To find the reciprocal of a rational expression--any rational expression--all you need to do is flip the numerator and the denominator.
Therefore, the correct answer is:
You can check this by multiplying the two expressions together and ensuring that your answer is .
Example Question #2 : How To Find The Reciprocal Of A Fraction
Find the reciprocal of the following expression:
To find the reciprocal of any fraction, you merely need to invert the numerator and denominator.
In this case, first you have to convert the mixed number into a fraction:
Therefore, the answer is:
Example Question #52 : Fractions
What is the least common denominator of and ?
To find the least common denominator of two numbers, it is easiest first to factor them into prime factors:
Now, you need to compare each number and choose the case in which the prime factor has the highest power. Therefore, since and are found only in , you will select those. You can take "either" . Finally, the in is the largest factor of . Your LCD is found by multiplying all of these together:
Example Question #54 : Fractions
Simplify:
To begin to solve this, you need to find the least common denominator of and . The easiest way to do this is to begin by factoring them into prime factors:
The LCD is found by selecting the largest power for each factor across the two values. Therefore, you will take ,, and from and the from the . Your LCD is therefore:
.
Now, apply this to your fractions: