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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. What causes 80% of errors on the math section of the GRE?
Not reading the problems carefully enough!
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.
Favorable Outcomes/Total Possible Outcomes
A radius

2. Define the mode of a set of numbers.
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 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.
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.
1. Given event A: A + notA = 1.

3. How do you solve a permutation?
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
4 angles are formed. Their sum is 360 degrees
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'.
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.

4. When 2 lines are perpendicular to each other - their intersection forms 4 angles. What degree are these 4 angles?
(a+b)(a-b)
90 degrees each.
1/x^n For example - 6-² = 1/6² = 1/36
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.

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

6. HIGH: How much of your times table should you know - for the GRE?
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
The value that appears most often in a data set.
It will be a great advantage on test day to have your times table memorized from 1 through 15.
S*v2

7. Explain the difference between handling a permutation versus a combination.
360 degrees
The value that appears most often in a data set.
1.7
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.

8. What is the formula to determine probability?
The average - mean - median - or mode.
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
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'.
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)

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

10. HIGH: Volume of a cube?
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
V=s³
Not reading the problems carefully enough!
Percentage Change = Difference/Original * 100

11. What is the equation for a group problem?
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
(x+y)²
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.
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

12. If something is possible but not certain - what is the numeric range of probability of it happening?
80%
Between 0 and 1.
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
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.

13. HIGH: What is the order of math operations - and the mnemonic to remember it?
2r
A circle'S perimeter is roughly 3x its diameter (the formula is pd).
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
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

14. HIGH: List the two most common side ratios for right triangles
25%
3:4:5 5:12:13
180 degrees.
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.

15. HIGH: What is the side ratio for a 30:60:90 triangle?
V=pr²h (This is just the area multiplied by the height)
3:4:5 5:12:13
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
Not reading the problems carefully enough!

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

17. Define 'proportionate' values
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
(x+y)²
An integer is divisible by 5 if its units digit is either 0 or 5.
An integer is divisible by 4 if its last two digits form a number that'S divisible by 4. For example - 712 is divisible by 4 because its last two digits (12) is divisible by 4.

18. What degree angle is a line?
6
360 degrees
The formula is a² + b² + c² = d² where a - b - c are the dimensions of the figure and d is the diagonal.
A line is a 180-degree angle.

19. What should you do BEFORE you start to solve a GRE math problem?

20. Explain how to use a 'Rate Pie'
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
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
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.
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

21. What is an 'equilateral' triangle?
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.
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.
4 angles are formed. Their sum is 360 degrees
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.

22. An integer is divisible by 9 if...
180 degrees.
x² -2xy + y²
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
An integer is divisible by 9 if the sum of its digits is divisible by 9.

23. HIGH: What is the unfactored version of (x+y)² ?
An integer is divisible by 2 if its units digit is divisible by 2.
180 degrees.
x² + 2xy + y²
Percentage Change = Difference/Original * 100

24. HIGH: What is the mode?
x² + 2xy + y²
2pr -or- pd
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.
The value that appears most often in a data set.

25. How do you calculate the probability of two events in a row? (Probability of A and B)
Probability A * Probability B
(x+y)(x-y)
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.
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.

26. An integer is divisible by 5 if...
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.
The average - mean - median - or mode.
An integer is divisible by 5 if its units digit is either 0 or 5.
60%

27. What do permutation problems often ask for?
Arrangements - orders - schedules - or lists.
A=pr²
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.
Find a common denominator and make equivalent fractions. Then add or subtract.

28. HIGH: Describe how to deal with 2 sets of parentheses.
An integer is divisible by 4 if its last two digits form a number that'S divisible by 4. For example - 712 is divisible by 4 because its last two digits (12) is divisible by 4.
(x+y)²
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)+
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.

29. HIGH: What is the factored version of (x+y)(x-y) ?
A line is a 180-degree angle.
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
x²-y²
1.4

30. In a coordinate system - identify the quadrants and describe their location.
S*v2
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.
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.
A 90-degree angle.

31. What number goes on the bottom of a probability fraction?
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 total # of possible outcomes.
A 90-degree angle.
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.

32. HIGH: What is the Pythagorean theorem?

33. HIGH: How do you calculate the circumference of a circle?
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
'Big' angles and 'Small' angles.
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
2pr -or- pd

34. Convert to a percentage: 3/5
Turn the second fraction upside down (find its reciprocal) and multiply. Example: 2/3 ÷ 4/5 = 2/3 * 5/4
Example: 1 < x < 10
60%
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.

35. What is a 'Right' angle?
A 90-degree angle.
6
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.
The # falling in the center of an ordered data set

36. Convert to a percentage: 2/5
40%
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
1.4
'Big' angles and 'Small' angles.

37. HIGH: How do you calculate the length of an arc?

38. Simplify this: v32
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.
An integer is divisible by 4 if its last two digits form a number that'S divisible by 4. For example - 712 is divisible by 4 because its last two digits (12) is divisible by 4.
180 degrees

39. Area of a parallelogram?
Invert the second fraction (reciprocal) and multiply
The value that appears most often in a data set.
Bh
A circle'S perimeter is roughly 3x its diameter (the formula is pd).

40. HIGH: What is the factored version of x² + 2xy + y² ?
180 degrees.
(x+y)²
Invert the second fraction (reciprocal) and multiply
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.

41. v4 =
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.
2
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.
'Big' angles and 'Small' angles.

42. How do you add or subtract fractions?
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.
Find a common denominator and make equivalent fractions. Then add or subtract.
1.4
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.

43. HIGH: What is a 'Right isosceles' triangle?
1. Given event A: A + notA = 1.
This triangle is a square divided along its diagonal. Interior angles are 90:45:45 degrees. The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.
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

44. HIGH: What is the formula for the diagonal of any square?
Between 0 and 1.
An integer is divisible by 5 if its units digit is either 0 or 5.
S*v2
180 degrees

45. HIGH: What is the unfactored version of (x-y)² ?
This triangle is a square divided along its diagonal. Interior angles are 90:45:45 degrees. The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
x² -2xy + y²
360 degrees
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.

46. An integer is divisible by 2 if...
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
Bh
An integer is divisible by 2 if its units digit is divisible by 2.
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.

47. An integer is divisible by 3 if...
Not reading the problems carefully enough!
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.
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.
1

48. What'S the most important thing to remember about charts you'll see on the GRE?
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.
x² + 2xy + y²
Bh
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.

49. If something is certain to happen - how is the probability of this event expressed mathematically?
1/1
360 degrees
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
4 angles are formed. Their sum is 360 degrees

50. HIGH: What numbers does ETS hope you'll forget to consider - for quant comp questions?
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions
A 90-degree angle.
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.
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.