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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. How do you calculate the probability of EITHER one event OR another event happening? (Probability of A or B)
2r
2 - 14 - and 34. So - a Bell - standard deviation - or normal distribution curve would be segmented: | 2% | 14% | 34% |average score| 34% | 14% | 2% |
The # falling in the center of an ordered data set
Probability A + Probability B

2. What is the equation for a group problem?
A radius
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.
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
(x-y)²

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

4. Convert to a percentage: 1/4
25%
Not necessarily. This is a trick question - because x could be either positive or negative.
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.
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.

5. What kind of triangle is this: has two sides of equal length - and a 90 degree angle?
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.
25%
A triangle in which one of the three interior angles is 90 degrees.
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

6. Probability Formula
Favorable Outcomes/Total Possible Outcomes
40%
The formula is a² + b² + c² = d² where a - b - c are the dimensions of the figure and d is the diagonal.
The value that appears most often in a data set.

7. HIGH: Rough est. of v2 =
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
(0 -0)
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
1.4

8. HIGH: How do you multiply and divide square roots?
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.
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
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%.

9. If something is possible but not certain - what is the numeric range of probability of it happening?
Slope = rise/run. Find the change in y-coordinates (rise) and the change in x-coordinates (run) to calculate.
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.
Between 0 and 1.
2pr -or- pd

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

11. The probability of an event happening and the probability of an event NOT happening must add up to what number?
Find the total - or whole - first - and then set up a Ratio Box.
1. Given event A: A + notA = 1.
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.
1.4

12. HIGH: x^-n is equal to
The # falling in the center of an ordered data set
360 degrees
1/x^n For example - 6-² = 1/6² = 1/36
4 angles are formed. Their sum is 360 degrees

13. HIGH: What is a '30:60:90' triangle?
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.
S*v2
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
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.

14. HIGH: what is the side ratio for a Right Isosceles triangle?
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
Probability A + Probability B
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
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.

15. What are 'vertical angles'?
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.
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.
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.

16. HIGH: Area of a circle
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.
An integer is divisible by 9 if the sum of its digits is divisible by 9.
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.
A=pr²

17. Explain how to solve for 7/¼
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.
This equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2

18. HIGH: Describe how to deal with 2 sets of parentheses.
Probability A + Probability B
2r
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.

19. When 2 lines are perpendicular to each other - their intersection forms 4 angles. What degree are these 4 angles?
1.7
90 degrees each.
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.
1/x^n For example - 6-² = 1/6² = 1/36

20. HIGH: What is the unfactored version of (x+y)² ?
V=s³
A radius
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.
x² + 2xy + y²

21. HIGH: What is the unfactored version of (x-y)² ?
Slope = rise/run. Find the change in y-coordinates (rise) and the change in x-coordinates (run) to calculate.
1.4
(a+b)(a-b)
x² -2xy + y²

22. HIGH: How much of your times table should you know - for the GRE?
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
360 degrees
180 degrees.
It will be a great advantage on test day to have your times table memorized from 1 through 15.

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

24. How do you divide fractions?
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
Invert the second fraction (reciprocal) and multiply
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.
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.

25. Does order matter for a permutation? How about for a combination?
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
The value that appears most often in a data set.
Order does matter for a permutation - but does not matter for a combination.
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.

26. Define a factorial of a number - and how it is written.
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.
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.
x² + 2xy + y²
'Big' angles and 'Small' angles.

27. What'S a handy rough estimate for a circle'S perimeter - if you know it'S diameter?

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

29. How is a range expressed with inequalities?
Multiply numerator times numerator and denominator times denominator.
Example: 1 < x < 10
Add the exponents - retain the base. for example - x² + x5 = x²+5 = x7
An integer is divisible by 9 if the sum of its digits is divisible by 9.

30. What is a 'Right' triangle?
25%
Probability A + Probability B
A triangle in which one of the three interior angles is 90 degrees.
A circle'S perimeter is roughly 3x its diameter (the formula is pd).

31. How many angles are formed when 2 lines intersect? and what is the sum of these angles?
2pr -or- pd
For RIGHT triangles only: c² = a² + b² 'c' is the length of the hypotenuse; 'a' and 'b' are the other two sides ('legs')
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.
4 angles are formed. Their sum is 360 degrees

32. HIGH: What is the formula for the diagonal of any square?
S*v2
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5
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'.
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

33. In a coordinate system - identify the quadrants and describe their location.
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.
It will be a great advantage on test day to have your times table memorized from 1 through 15.
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.
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.

34. An integer is divisible by 2 if...
An integer is divisible by 2 if its units digit is divisible by 2.
Arrangements - orders - schedules - or lists.
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)+
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2

35. HIGH: What is the factored version of (x+y)(x-y) ?
'Big' angles and 'Small' angles.
4 angles are formed. Their sum is 360 degrees
x²-y²
Example: 1 < x < 10

36. An integer is divisible by 5 if...
2 - 14 - and 34. So - a Bell - standard deviation - or normal distribution curve would be segmented: | 2% | 14% | 34% |average score| 34% | 14% | 2% |
V=s³
An integer is divisible by 5 if its units digit is either 0 or 5.
180 degrees.

37. List two odd behaviors of exponents
An integer is divisible by 2 if its units digit is divisible by 2.
This equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28
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.
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.

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

39. What do combination problems usually ask for?
(x-y)²
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
Groups - teams - or committees.
Find the total - or whole - first - and then set up a Ratio Box.

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

41. HIGH: how do you calculate a diagonal inside a 3-dimensional rectangular box?
6
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.
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
The formula is a² + b² + c² = d² where a - b - c are the dimensions of the figure and d is the diagonal.

42. HIGH: To divide powers with the same base...
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5
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.
Invert the second fraction (reciprocal) and multiply
'Big' angles and 'Small' angles.

43. What degree angle is a line?
Groups - teams - or committees.
A line is a 180-degree angle.
(0 -0)
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.

44. Explain the special properties of zero.
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
2pr -or- pd
Add the exponents - retain the base. for example - x² + x5 = x²+5 = x7
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.

45. Explain how to calculate an average (arithmetic mean)
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.
2
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3
Multiply numerator times numerator and denominator times denominator.

46. How do you calculate the probability of two events in a row? (Probability of A and B)
For RIGHT triangles only: c² = a² + b² 'c' is the length of the hypotenuse; 'a' and 'b' are the other two sides ('legs')
Probability A * Probability B
Turn the second fraction upside down (find its reciprocal) and multiply. Example: 2/3 ÷ 4/5 = 2/3 * 5/4
Find a common denominator and make equivalent fractions. Then add or subtract.

47. An integer is divisible by 9 if...
An integer is divisible by 9 if the sum of its digits is divisible by 9.
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions
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

48. HIGH: Volume of a cylinder?
(a+b)(a-b)
Between 0 and 1.
For RIGHT triangles only: c² = a² + b² 'c' is the length of the hypotenuse; 'a' and 'b' are the other two sides ('legs')
V=pr²h (This is just the area multiplied by the height)

49. In a coordinate system - what is the origin?
(0 -0)
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.
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.
A triangle in which one of the three interior angles is 90 degrees.

50. HIGH: Describe and define three expressions of quadratic equations - in both factored and unfactored forms. Know these cold.
S²
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.
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.
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