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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 is one misleading characteristic of quadratic equations that will be exploited on the GRE?
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.
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.
An integer is divisible by 2 if its units digit is divisible by 2.
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. HIGH: x^-n is equal to
1/x^n For example - 6-² = 1/6² = 1/36
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
V=pr²h (This is just the area multiplied by the height)
Percentage Change = Difference/Original * 100

3. What is the 'distributive law'?
A triangle in which one of the three interior angles is 90 degrees.
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.
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.

4. Define the median of a set of numbers - and how to find it for an odd and even number of values in a set.

5. What is the key to dealing with ratio questions?
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
Find the total - or whole - first - and then set up a Ratio Box.
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.
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.

6. What is the sum of any 'big' angle and any 'Small' angle?
2 - 14 - and 34. So - a Bell - standard deviation - or normal distribution curve would be segmented: | 2% | 14% | 34% |average score| 34% | 14% | 2% |
180 degrees.
40%
Multiply numerator times numerator and denominator times denominator.

7. HIGH: What is the factored version of (x+y)(x-y) ?
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.
x²-y²
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
Slope = rise/run. Find the change in y-coordinates (rise) and the change in x-coordinates (run) to calculate.

8. HIGH: What is the median?
The # falling in the center of an ordered data set
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.
The total # of possible outcomes.
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. What causes 80% of errors on the math section of the GRE?
Not reading the problems carefully enough!
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.
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.
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.

10. HIGH: What is the mode?
(0 -0)
A=pr²
The value that appears most often in a data set.
For RIGHT triangles only: c² = a² + b² 'c' is the length of the hypotenuse; 'a' and 'b' are the other two sides ('legs')

11. HIGH: Describe how to deal with 2 sets of parentheses.
An integer is divisible by 8 if its last three digits form a number that'S divisible by 8. For example - 11 -640.
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
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)+
4 angles are formed. Their sum is 360 degrees

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

13. HIGH: What is a '30:60:90' triangle?
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
Find the total - or whole - first - and then set up a Ratio Box.
Favorable Outcomes/Total Possible Outcomes
(0 -0)

14. HIGH: List the two most common side ratios for right triangles
60%
3:4:5 5:12:13
1
(x+y)²

15. HIGH: Simplify this: v75/v27
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.
Favorable Outcomes/Total Possible Outcomes
Order does matter for a permutation - but does not matter for a combination.
(0 -0)

16. HIGH: what is the side ratio for a Right Isosceles triangle?
(x-y)²
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
Order does matter for a permutation - but does not matter for a combination.
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.

17. Convert to a percentage: 2/5
180 degrees.
40%
Between 0 and 1.
(a+b)(a-b)

18. HIGH: Volume of a cube?
V=s³
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
Bh
A radius

19. HIGH: To divide powers with the same base...
Multiply numerator times numerator and denominator times denominator.
60%
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5

20. Probability Formula
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.
Favorable Outcomes/Total Possible Outcomes
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3
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.

21. Area of a square?
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.
S²
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

22. For a bell curve - what three terms might be used to describe the number in the middle?
The average - mean - median - or mode.
x² -2xy + y²
80%
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.

23. An integer is divisible by 3 if...
x² -2xy + y²
Turn the second fraction upside down (find its reciprocal) and multiply. Example: 2/3 ÷ 4/5 = 2/3 * 5/4
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.
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.

24. 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.
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.
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.
x² + 2xy + y²

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
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.
1. Given event A: A + notA = 1.
(x-y)²

26. Define 'proportionate' values
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
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
1. Given event A: A + notA = 1.
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.

27. HIGH: Rough est. of v1 =
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.
2pr -or- pd
x² -2xy + y²
1

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

29. Explain the special properties of zero.
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5
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.
2

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

31. HIGH: Area of a triangle?
The total # of possible outcomes.
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
1.4
x² + 2xy + y²

32. An integer is divisible by 9 if...
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
6
An integer is divisible by 9 if the sum of its digits is divisible by 9.
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.

33. Simplify this: v32
Invert the second fraction (reciprocal) and multiply
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.
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.
1.4

34. An integer is divisible by 2 if...
An integer is divisible by 2 if its units digit is divisible by 2.
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.
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%.
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.

35. HIGH: How do you multiply and divide square roots?
1/x^n For example - 6-² = 1/6² = 1/36
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.

36. What is the factored version of x² -2xy + y² ?
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 average - mean - median - or mode.
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.
(x-y)²

37. HIGH: Area of a circle
A=pr²
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.
6
Favorable Outcomes/Total Possible Outcomes

38. HIGH: Describe and define three expressions of quadratic equations - in both factored and unfactored forms. Know these cold.
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
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.
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=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.

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

40. How do you calculate the probability of EITHER one event OR another event happening? (Probability of A or B)
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')
The value that appears most often in a data set.
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.

41. How do you calculate the percentage of change?
The average - mean - median - or mode.
Percentage Change = Difference/Original * 100
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.
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.

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

43. HIGH: What is the unfactored version of x²-y² ?
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
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.
An integer is divisible by 8 if its last three digits form a number that'S divisible by 8. For example - 11 -640.
(x+y)(x-y)

44. Define the range of a set of numbers.
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
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.
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
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.

45. HIGH: What numbers does ETS hope you'll forget to consider - for quant comp questions?
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions
Add the exponents - retain the base. for example - x² + x5 = x²+5 = x7
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2

46. Convert to a percentage: 3/5
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.
2 - 14 - and 34. So - a Bell - standard deviation - or normal distribution curve would be segmented: | 2% | 14% | 34% |average score| 34% | 14% | 2% |
60%
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

47. HIGH: What is the Pythagorean theorem?

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

49. Diameter of a circle?
2r
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.
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.
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions

50. a² - b² is equal to
(a+b)(a-b)
A 90-degree angle.
80%
1