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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. Explain the difference between a digit and a number.

2. How do you calculate the probability of two events in a row? (Probability of A and B)
Absolute value is a number'S distance away from zero on the number line. It is always positive - regardless of whether the number is positive or negative. It is represented with | |. For example - |-5| = 5 - and |5| = 5.
A triangle in which one of the three interior angles is 90 degrees.
Order does matter for a permutation - but does not matter for a combination.
Probability A * Probability B

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

4. HIGH: What is the factored version of x² + 2xy + y² ?
1/1
(x+y)²
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.
The # falling in the center of an ordered data set

5. HIGH: How do you multiply and divide square roots?
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 6 if it'S divisible by BOTH 2 and 3.
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.

6. What is the equation for a group problem?
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
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.
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
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.

7. What causes 80% of errors on the math section of the GRE?
Not reading the problems carefully enough!
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.
y = mx + b -- where: x -y are the coordinates of any point on the line (allows you to locate) m is the slope of the line b is the intercept (where the line crosses the y-axis) Sometimes on the GRE - 'a' is substituted for 'm' - as in 'y = ax + b'.
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%.

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

9. HIGH: Simplify this: v75/v27
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.
x² -2xy + y²
y = mx + b -- where: x -y are the coordinates of any point on the line (allows you to locate) m is the slope of the line b is the intercept (where the line crosses the y-axis) Sometimes on the GRE - 'a' is substituted for 'm' - as in 'y = ax + b'.
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.

10. Explain how to use a 'Rate Pie'
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
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
180 degrees.
40%

11. HIGH: How much of your times table should you know - for the GRE?
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
180 degrees
It will be a great advantage on test day to have your times table memorized from 1 through 15.

12. How do you calculate the probability of EITHER one event OR another event happening? (Probability of A or B)
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
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.
Probability A + Probability B
Not reading the problems carefully enough!

13. HIGH: Define the 'Third side' rule for triangles

14. HIGH: What is the unfactored version of (x+y)² ?
x² + 2xy + y²
(x+y)²
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3
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.

15. HIGH: Rough est. of v2 =
2r
360 degrees
1.4
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.

16. If something is certain to happen - how is the probability of this event expressed mathematically?
A radius
3:4:5 5:12:13
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
1/1

17. An integer is divisible by 9 if...
6
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
360 degrees
An integer is divisible by 9 if the sum of its digits is divisible by 9.

18. How do you divide fractions?
1.7
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
Invert the second fraction (reciprocal) and multiply
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.

19. Does order matter for a permutation? How about for a combination?
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
Order does matter for a permutation - but does not matter for a combination.
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.

20. HIGH: What must be true before a quadratic equation can be solved?

21. HIGH: What is the factored version of (x+y)(x-y) ?
x²-y²
1/1
Absolute value is a number'S distance away from zero on the number line. It is always positive - regardless of whether the number is positive or negative. It is represented with | |. For example - |-5| = 5 - and |5| = 5.
Between 0 and 1.

22. What'S one way to avoid mistakes on algebra questions in the GRE?

23. a² - b² is equal to
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.
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
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.
(a+b)(a-b)

24. Explain how to use an 'Average Pie'
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.
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.
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.
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.

25. In a coordinate system - what is the origin?
6
Invert the second fraction (reciprocal) and multiply
(0 -0)
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.

26. HIGH: What is the median?
6
The # falling in the center of an ordered data set
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.
Order does matter for a permutation - but does not matter for a combination.

27. Define a factorial of a number - and how it is written.
The # falling in the center of an ordered data set
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.
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.
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3

28. How do you calculate the percentage of change?
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
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.

29. HIGH: What is the unfactored version of (x-y)² ?
x² -2xy + y²
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions
1. Given event A: A + notA = 1.
Use the FOIL method: First - Outer - Inner - Last. This simply means to multiply every term in the first parentheses by every term in the second parentheses. Example: (x+4)(x+3) = First: (xx) + Outer: (x3) + Inner: (4x) + Last: (43) = (xx)+(x3)+(x4)+

30. Define the mode of a set of numbers.
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
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.
Absolute value is a number'S distance away from zero on the number line. It is always positive - regardless of whether the number is positive or negative. It is represented with | |. For example - |-5| = 5 - and |5| = 5.
(x+y)²

31. What do combination problems usually ask for?
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.
60%
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.
Groups - teams - or committees.

32. How do you multiply fractions?
Not reading the problems carefully enough!
Multiply numerator times numerator and denominator times denominator.
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.
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.

33. HIGH: What is the equation of a line?

34. Define 'proportionate' values
A 90-degree angle.
(x+y)(x-y)
(x-y)²
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.

35. The three interior angles of a triangle add up to...
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3
180 degrees
25%
1. Figure out how many slots you have (i.e. there are 3 winning positions in a race - 1st - 2nd - and 3rd) 2. Write down the number of possible options for each slot (i.e. 5 runners in the race - so 5 options for the 1st slot - 4 options for the 2nd

36. What is the name of a line that extends from the center of a circle to the edge of a circle?
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
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
A radius
Length of an Arc = (n/360)(2pr) - where 'n' equals the central angle (the angle formed by the two edge radii of the arc). For example: if n=60 - then n/360 = 1/6 - which means the arc formed by the 60-degree central angle will be 1/6 of the circle'S

37. If something is possible but not certain - what is the numeric range of probability of it happening?
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.
Favorable Outcomes/Total Possible Outcomes
Arrangements - orders - schedules - or lists.
Between 0 and 1.

38. How do you solve a permutation?
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.
The total # of possible outcomes.
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
1. Figure out how many slots you have (i.e. there are 3 winning positions in a race - 1st - 2nd - and 3rd) 2. Write down the number of possible options for each slot (i.e. 5 runners in the race - so 5 options for the 1st slot - 4 options for the 2nd

39. HIGH: What is the Pythagorean theorem?

40. How do you add or subtract fractions?
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.
Find a common denominator and make equivalent fractions. Then add or subtract.
(0 -0)
4 angles are formed. Their sum is 360 degrees

41. List two odd behaviors of exponents
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.
The formula is a² + b² + c² = d² where a - b - c are the dimensions of the figure and d is the diagonal.
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
40%

42. What is the key to dealing with ratio questions?
Find the total - or whole - first - and then set up a Ratio Box.
6
'Big' angles and 'Small' angles.
y = mx + b -- where: x -y are the coordinates of any point on the line (allows you to locate) m is the slope of the line b is the intercept (where the line crosses the y-axis) Sometimes on the GRE - 'a' is substituted for 'm' - as in 'y = ax + b'.

43. HIGH: how do you calculate a diagonal inside a 3-dimensional rectangular box?
The formula is a² + b² + c² = d² where a - b - c are the dimensions of the figure and d is the diagonal.
3:4:5 5:12:13
Length of an Arc = (n/360)(2pr) - where 'n' equals the central angle (the angle formed by the two edge radii of the arc). For example: if n=60 - then n/360 = 1/6 - which means the arc formed by the 60-degree central angle will be 1/6 of the circle'S
Between 0 and 1.

44. Explain how to calculate an average (arithmetic mean)
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3
Add the exponents - retain the base. for example - x² + x5 = x²+5 = x7
1.7
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.

45. HIGH: x^-n is equal to
1/x^n For example - 6-² = 1/6² = 1/36
40%
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.
By Plugging In an actual value for the variable(s). This will be quicker - more accurate - you'll avoid built-in traps - and you can use the calculator. When Plugging In - use simple numbers but avoid 1 and 0.

46. HIGH: How do you calculate the circumference of a circle?
2pr -or- pd
Multiply numerator times numerator and denominator times denominator.
It will be a great advantage on test day to have your times table memorized from 1 through 15.
Order does matter for a permutation - but does not matter for a combination.

47. List all the prime numbers that are less than 30:
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
x² + 2xy + y²
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions
This is an equilateral triangle that has been divided along its height. Interior angles are 30:60:90 degrees. Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse. This allows you to deduce any side - given

48. Explain the difference between handling a permutation versus a combination.
6
Invert the second fraction (reciprocal) and multiply
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.
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.

49. HIGH: How do you multiply powers with the same base?
1.7
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
Add the exponents - retain the base. for example - x² + x5 = x²+5 = x7
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3

50. Probability Formula
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.
An integer is divisible by 5 if its units digit is either 0 or 5.
Favorable Outcomes/Total Possible Outcomes