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

2. The probability of an event happening and the probability of an event NOT happening must add up to what number?
1. Given event A: A + notA = 1.
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
V=pr²h (This is just the area multiplied by the height)
This equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28

3. How do you solve a permutation?
The average - mean - median - or mode.
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.
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
V=pr²h (This is just the area multiplied by the height)

4. Explain how to calculate an average (arithmetic mean)
A radius
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3
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
V=pr²h (This is just the area multiplied by the height)

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

6. HIGH: Rough est. of v1 =
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%.
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
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

7. What is the factored version of x² -2xy + y² ?
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.
(0 -0)
360 degrees
(x-y)²

8. How many angles are formed when 2 lines intersect? and what is the sum of these angles?
80%
4 angles are formed. Their sum is 360 degrees
A radius
(x-y)²

9. How do you divide fractions?
Invert the second fraction (reciprocal) and multiply
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
40%

10. When 2 lines are perpendicular to each other - their intersection forms 4 angles. What degree are these 4 angles?
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
(a+b)(a-b)
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.
90 degrees each.

11. What is the key to dealing with ratio questions?
This equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28
Find the total - or whole - first - and then set up a Ratio Box.
1.4
Percentage Change = Difference/Original * 100

12. HIGH: List the two most common side ratios for right triangles
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.
A circle'S perimeter is roughly 3x its diameter (the formula is pd).
Groups - teams - or committees.
3:4:5 5:12:13

13. What is the 'distributive law'?
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.
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.
A triangle in which one of the three interior angles is 90 degrees.
(x+y)²

14. What are 'vertical angles'?
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
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
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. 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

15. Probability Formula
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.
Favorable Outcomes/Total Possible Outcomes
V=pr²h (This is just the area multiplied by the height)
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

16. HIGH: What is the side ratio for a 30:60:90 triangle?
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 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.
Example: 1 < x < 10
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.

17. HIGH: what is the side ratio for a Right Isosceles triangle?
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
Not necessarily. This is a trick question - because x could be either positive or negative.
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
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.

18. What is the sum of any 'big' angle and any 'Small' angle?
For RIGHT triangles only: c² = a² + b² 'c' is the length of the hypotenuse; 'a' and 'b' are the other two sides ('legs')
180 degrees.
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 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.

19. HIGH: Volume of a cylinder?
V=pr²h (This is just the area multiplied by the height)
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.
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5
A circle'S perimeter is roughly 3x its diameter (the formula is pd).

20. What is a 'Right' angle?
(a+b)(a-b)
A 90-degree angle.
Favorable Outcomes/Total Possible Outcomes
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.

21. What is the name of a line that extends from the center of a circle to the edge of a circle?
V=pr²h (This is just the area multiplied by the height)
A radius
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
V=s³

22. HIGH: Describe how to deal with 2 sets of parentheses.
A line is a 180-degree angle.
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
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.
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)+

23. HIGH: Volume of a cube?
x² + 2xy + y²
V=s³
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
A radius

24. HIGH: Describe and define three expressions of quadratic equations - in both factored and unfactored forms. Know these cold.
An integer is divisible by 5 if its units digit is either 0 or 5.
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
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
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

25. What is the equation for a group problem?
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
90 degrees each.
Add the exponents - retain the base. for example - x² + x5 = x²+5 = x7

26. How do you calculate the percentage of change?
Percentage Change = Difference/Original * 100
Find the total - or whole - first - and then set up a Ratio Box.
Multiply numerator times numerator and denominator times denominator.
A=pr²

27. Define the range of a set of numbers.
V=pr²h (This is just the area multiplied by the height)
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
Order does matter for a permutation - but does not matter for a combination.

28. How do you add or subtract fractions?
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.
x² + 2xy + y²
Find a common denominator and make equivalent fractions. Then add or subtract.
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

29. Area of a square?
Between 0 and 1.
S²
For RIGHT triangles only: c² = a² + b² 'c' is the length of the hypotenuse; 'a' and 'b' are the other two sides ('legs')
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.

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

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

32. List two odd behaviors of exponents
The average - mean - median - or mode.
1
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.
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.

33. HIGH: What is the median?
Bh
The # falling in the center of an ordered data set
Arrangements - orders - schedules - or lists.
60%

34. What kind of triangle is this: has two sides of equal length - and a 90 degree angle?
(x+y)²
Find the total - or whole - first - and then set up a Ratio Box.
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.
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.

35. Diameter of a circle?
1. Given event A: A + notA = 1.
V=pr²h (This is just the area multiplied by the height)
2r
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.

36. An integer is divisible by 5 if...
40%
The value that appears most often in a data set.
An integer is divisible by 5 if its units digit is either 0 or 5.
1/x^n For example - 6-² = 1/6² = 1/36

37. What is an 'equilateral' triangle?
4 angles are formed. Their sum is 360 degrees
60%
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.
An integer is divisible by 5 if its units digit is either 0 or 5.

38. HIGH: Simplify this: v75/v27
Probability A + Probability B
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
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.
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)

39. HIGH: How do you get rid of the fraction in this equation: 5x + 3/2 = 7x
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
Invert the second fraction (reciprocal) and multiply
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=pr²

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

41. Define the mode of a set of numbers.
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 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 angles are formed. Their sum is 360 degrees
(a+b)(a-b)

42. HIGH: Rough est. of v2 =
1.4
x²-y²
2
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.

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

44. The three interior angles of a triangle add up to...
180 degrees
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.
Groups - teams - or committees.
An integer is divisible by 8 if its last three digits form a number that'S divisible by 8. For example - 11 -640.

45. HIGH: Area of a circle
Add the exponents - retain the base. for example - x² + x5 = x²+5 = x7
1. Given event A: A + notA = 1.
A=pr²
A triangle in which one of the three interior angles is 90 degrees.

46. How do you multiply fractions?
Multiply numerator times numerator and denominator times denominator.
2pr -or- pd
3:4:5 5:12:13
(x-y)²

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

48. Convert to a percentage: 4/5
2
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.
80%
40%

49. Convert to a percentage: 2/5
60%
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.
Not reading the problems carefully enough!
40%

50. HIGH: What is the unfactored version of (x+y)² ?
(x-y)²
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions
x² + 2xy + y²
2 - 14 - and 34. So - a Bell - standard deviation - or normal distribution curve would be segmented: | 2% | 14% | 34% |average score| 34% | 14% | 2% |