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GRE High Frequency Math Terms

Subjects : gre, math

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. a² - b² is equal to
Find the total - or whole - first - and then set up a Ratio Box.
(a+b)(a-b)
1. Given event A: A + notA = 1.
Between 0 and 1.

2. How precise do you need to be - using p on the GRE?

3. Explain how to use an 'Average Pie'
x² + 2xy + y²
PEMDAS (Please Excuse My Dear Aunt Sally): P = Parentheses. Solve anything inside of parentheses first. E = Exponents. Solve these second. MD = Multiplication - Division. From left to right - do all multiplication and division during one step through
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.
Invert the second fraction (reciprocal) and multiply

4. What is a 'Right' angle?
A median is the middle value of a set of numbers. For an odd number of values - it'S simply the middle number. For an even number of values - take the average of the center two values.
A 90-degree angle.
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
Not necessarily. This is a trick question - because x could be either positive or negative.

5. An integer is divisible by 9 if...
1/1
A(b+c) = ab + ac a(b-c) = ab - ac - For example - 12(66) + 12(24) is the same as 12(66+24) - or 12(90) = 1 -080.
An integer is divisible by 9 if the sum of its digits is divisible by 9.
'Big' angles and 'Small' angles.

6. HIGH: What is the Pythagorean theorem?

7. What number goes on the bottom of a probability fraction?
A triangle in which one of the three interior angles is 90 degrees.
The total # of possible outcomes.
The equation must be set equal to zero. If during the test one appears that'S not - before you can solve it you must first manipulate it so it is equal to zero.
25%

8. If something is possible but not certain - what is the numeric range of probability of it happening?
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.
The factorial of a number is that number times every positive whole number smaller than that number - down to 1. Example: 6! means the factorial of 6 - which = 65432*1 = 720.
2pr -or- pd
Between 0 and 1.

9. List two odd behaviors of exponents
The factorial of a number is that number times every positive whole number smaller than that number - down to 1. Example: 6! means the factorial of 6 - which = 65432*1 = 720.
Multiply each numerator by the other fraction'S denominator. Example: 3/7 and 7/12. Multiply 312 = 36 - and 77 = 49. If you completed the full calculation - you'd also cross-multiply the denominators - but you don'T have to in order to compare values
1. Raising a fraction (between 0 and 1) to a power greater than 1 results in a SMALLER number. For example: (1/2)² = 1/4. 2. A number raised to the 0 power is 1 - no matter what the number is. For example: 1 -287° = 1.
(0 -0)

10. Explain the difference between handling a permutation versus a combination.
A line is a 180-degree angle.
If order matters - then you have a permutation -- do NOT divide. If order does NOT matter - then you have a combination -- divide by the factorial of the number of available slots.
The length of any one side of a triangle must be less than the sum of the other two sides. It must also be greater than the difference between the other two sides. So - 'A' will always be < B+C - and > B-C or C-B.
A radius

11. Convert to a percentage: 2/5
That they often have not just one answer - but two. For example - solving x² -10x + 24 = 0 factors to (x-4)(x-6)=0 - which means x could equal either 4 or 6. Just accept it.
40%
1.4
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.

12. What'S the most important thing to remember about charts you'll see on the GRE?
That - unlike a normal chart - they are constructed to HIDE information or make it HARDER to understand. Be sure to scroll down - read everything - and look carefully for hidden information - asterisks - footnotes - small print - and funny units.
2
2 - 14 - and 34. So - a Bell - standard deviation - or normal distribution curve would be segmented: | 2% | 14% | 34% |average score| 34% | 14% | 2% |
PEMDAS (Please Excuse My Dear Aunt Sally): P = Parentheses. Solve anything inside of parentheses first. E = Exponents. Solve these second. MD = Multiplication - Division. From left to right - do all multiplication and division during one step through

13. How do you calculate the probability of two events in a row? (Probability of A and B)
Probability A * Probability B
The length of any one side of a triangle must be less than the sum of the other two sides - and greater than the difference between the other two sides.
S*v2
Slope = rise/run. Find the change in y-coordinates (rise) and the change in x-coordinates (run) to calculate.

14. HIGH: Rough est. of v3 =
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
1
A line is a 180-degree angle.
1.7

15. The three interior angles of a triangle add up to...
Zero is even. It is an integer. It is neither positive nor negative. Zero multiplied by any other number = zero. You cannot divide by zero.
A median is the middle value of a set of numbers. For an odd number of values - it'S simply the middle number. For an even number of values - take the average of the center two values.
180 degrees
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.

16. In a coordinate system - what is the origin?
V75 = v253 = 5v3 - and v27 = v93 = 3v3. So we have 5v3/3v3. The v3 in the top and bottom of the fraction cancel - leaving 5/3.
1/1
(0 -0)
A triangle in which one of the three interior angles is 90 degrees.

17. An integer is divisible by 3 if...
Find a common denominator and make equivalent fractions. Then add or subtract.
A digit is a number that makes up other numbers. There are ten digits: 0 -1 -2 -3 -4 -5 -6 -7 -8 -9. Every 'number' is made up of one or more digits. For example - the number 528 is made up of three digits - a 5 - a 2 - and an 8.
Multiply each numerator by the other fraction'S denominator. Example: 3/7 and 7/12. Multiply 312 = 36 - and 77 = 49. If you completed the full calculation - you'd also cross-multiply the denominators - but you don'T have to in order to compare values
An integer is divisible by 3 if the sum of its digits is divisible by 3. For example - adding the digits of the number 2 -145 (2+1+4+5) = 12 - which is divisible by 3.

18. What is the 'distributive law'?
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
A(b+c) = ab + ac a(b-c) = ab - ac - For example - 12(66) + 12(24) is the same as 12(66+24) - or 12(90) = 1 -080.
S*v2
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.

19. HIGH: Explain a method for quickly comparing fractions with different denominators - to determine which is larger.

20. HIGH: What is the order of math operations - and the mnemonic to remember it?
PEMDAS (Please Excuse My Dear Aunt Sally): P = Parentheses. Solve anything inside of parentheses first. E = Exponents. Solve these second. MD = Multiplication - Division. From left to right - do all multiplication and division during one step through
T = G1 + G2 - B + N Where T = Total G1 = first Group G2 = second Group B = members who are in Both groups N = members who are in Neither group
If order matters - then you have a permutation -- do NOT divide. If order does NOT matter - then you have a combination -- divide by the factorial of the number of available slots.
1. Figure out how many slots you have (i.e. you'Re supposed to bring home 3 different types of ice cream) 2. Write down the number of possible options for each slot (i.e. 5 flavors of ice cream at the store - 5 options for the 1st slot - 4 options fo

21. Define the range of a set of numbers.
Always read the answer choices first. Try to eliminate choices by ballparking or estimating. But watch out for 'Trap' answers that look temptingly correct at first glance.
Find the total - or whole - first - and then set up a Ratio Box.
The range is the difference between the biggest and smallest numbers in the set. Example: for the set {2 -6 -13 -3 -15 -4 -9} the smallest number is 2 - largest is 15 - so the range is 15-2=13.
Probability A * Probability B

22. Probability Formula
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.
Zero is even. It is an integer. It is neither positive nor negative. Zero multiplied by any other number = zero. You cannot divide by zero.
Multiply numerator times numerator and denominator times denominator.
Favorable Outcomes/Total Possible Outcomes

23. An integer is divisible by 4 if...

24. HIGH: How do you get rid of the fraction in this equation: 5x + 3/2 = 7x
'Big' angles and 'Small' angles.
Multiply all elements of both sides of the equation by 2 (the denominator of the fraction). This will produce 10x + 3 = 14x. Solve from there: 3 = 4x - x = 3/4.
A triangle in which one of the three interior angles is 90 degrees.
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions

25. What is one misleading characteristic of quadratic equations that will be exploited on the GRE?
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
An integer is divisible by 2 if its units digit is divisible by 2.
Percentage Change = Difference/Original * 100
That they often have not just one answer - but two. For example - solving x² -10x + 24 = 0 factors to (x-4)(x-6)=0 - which means x could equal either 4 or 6. Just accept it.

26. What is an 'equilateral' triangle?
Probability A * Probability B
A digit is a number that makes up other numbers. There are ten digits: 0 -1 -2 -3 -4 -5 -6 -7 -8 -9. Every 'number' is made up of one or more digits. For example - the number 528 is made up of three digits - a 5 - a 2 - and an 8.
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.
An integer is divisible by 2 if its units digit is divisible by 2.

27. Explain how to solve for 7/¼
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
This equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28
S²
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.

28. What is the 'Third side' rule for triangles?
x² -2xy + y²
The length of any one side of a triangle must be less than the sum of the other two sides - and greater than the difference between the other two sides.
1. Raising a fraction (between 0 and 1) to a power greater than 1 results in a SMALLER number. For example: (1/2)² = 1/4. 2. A number raised to the 0 power is 1 - no matter what the number is. For example: 1 -287° = 1.
V=s³

29. HIGH: What is the side ratio for a 30:60:90 triangle?
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.
1. Raising a fraction (between 0 and 1) to a power greater than 1 results in a SMALLER number. For example: (1/2)² = 1/4. 2. A number raised to the 0 power is 1 - no matter what the number is. For example: 1 -287° = 1.
(x+y)(x-y)

30. HIGH: Volume of a cylinder?
Find the total - or whole - first - and then set up a Ratio Box.
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
Arrangements - orders - schedules - or lists.
V=pr²h (This is just the area multiplied by the height)

31. What is the formula to determine probability?
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
Slope = rise/run. Find the change in y-coordinates (rise) and the change in x-coordinates (run) to calculate.
2pr -or- pd

32. HIGH: What is the unfactored version of x²-y² ?
S²
2
The total # of possible outcomes.
(x+y)(x-y)

33. When 2 lines are perpendicular to each other - their intersection forms 4 angles. What degree are these 4 angles?
90 degrees each.
Probability A * Probability B
Order does matter for a permutation - but does not matter for a combination.
The mode is the number in a set that occurs most frequently. Example: for the set {3 -6 -3 -8 -9 -3 -11} the number 3 appears most frequently so it is the mode.

34. How do you calculate the probability of EITHER one event OR another event happening? (Probability of A or B)
Multiply all elements of both sides of the equation by 2 (the denominator of the fraction). This will produce 10x + 3 = 14x. Solve from there: 3 = 4x - x = 3/4.
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
Probability A + Probability B
For RIGHT triangles only: c² = a² + b² 'c' is the length of the hypotenuse; 'a' and 'b' are the other two sides ('legs')

35. HIGH: Explain the process to solve '56 is what percent of 80?'

36. An integer is divisible by 5 if...
Find the total - or whole - first - and then set up a Ratio Box.
An integer is divisible by 5 if its units digit is either 0 or 5.
Percentage Change = Difference/Original * 100
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.

37. Explain how to use a 'Rate Pie'
This is similar to an Average Pie - and can be used for some story problems. Draw a circle. Top half holds the Distance or other Amount. Bottom left holds Time. Bottom right holds Rate. Rate * Time = Amount
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.
Slope = rise/run. Find the change in y-coordinates (rise) and the change in x-coordinates (run) to calculate.
(0 -0)

38. An integer is divisible by 8 if...

39. HIGH: What is the factored version of x² + 2xy + y² ?
(x+y)²
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.
Arrangements - orders - schedules - or lists.
The # falling in the center of an ordered data set

40. What causes 80% of errors on the math section of the GRE?
An isoceles right angle. Remember that interior angles are 90:45:45 degrees. The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
Not reading the problems carefully enough!
A digit is a number that makes up other numbers. There are ten digits: 0 -1 -2 -3 -4 -5 -6 -7 -8 -9. Every 'number' is made up of one or more digits. For example - the number 528 is made up of three digits - a 5 - a 2 - and an 8.
1. Factored: x² - y² Unfactored: (x+y)(x-y) 2. Factored: (x+y)² Unfactored: x² + 2xy + y² 3. Factored: (x-y)² Unfactored: x² - 2xy + y²

41. The three exterior angles of a triangle add up to...
360 degrees
(a+b)(a-b)
Calculate and add the areas of all of 6 its sides. Example: for a rectangle with dimensions 2 x 3 x 4 - there will be 2 sides each - for each combination of these dimensions. That is - 2 each of 2x3 - 2 each of 3x4 - and 2 each of 4x2.
'Big' angles and 'Small' angles.

42. Diameter of a circle?
x² -2xy + y²
2r
Bh
180 degrees.

43. How many angles are formed when 2 lines intersect? and what is the sum of these angles?
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.
4 angles are formed. Their sum is 360 degrees
x²-y²
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.

44. An integer is divisible by 2 if...
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.
360 degrees
An integer is divisible by 2 if its units digit is divisible by 2.
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2

45. If x² = 144 - does v144 = x?
1. Figure out how many slots you have (i.e. you'Re supposed to bring home 3 different types of ice cream) 2. Write down the number of possible options for each slot (i.e. 5 flavors of ice cream at the store - 5 options for the 1st slot - 4 options fo
Not necessarily. This is a trick question - because x could be either positive or negative.
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
For RIGHT triangles only: c² = a² + b² 'c' is the length of the hypotenuse; 'a' and 'b' are the other two sides ('legs')

46. For a bell curve - what three terms might be used to describe the number in the middle?
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.
1.7
That they often have not just one answer - but two. For example - solving x² -10x + 24 = 0 factors to (x-4)(x-6)=0 - which means x could equal either 4 or 6. Just accept it.
The average - mean - median - or mode.

47. An integer is divisible by 6 if...

48. Explain the difference between a digit and a number.

49. HIGH: Area of a triangle?
First - translate into clear math: 56 = x/100(80) ('56 is x one-hundredths of 80') = 56 = 80x/100 = 56 = 4x/5 Divide both sides by 4/5 (multiply by 5/4) 70 = x - so 70%.
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
(x+y)²
Between 0 and 1.

50. How do you divide fractions?
Example: 1 < x < 10
Invert the second fraction (reciprocal) and multiply
The average - mean - median - or mode.
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.