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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. HIGH: What is the unfactored version of (x+y)² ?
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.
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
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

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.
(x+y)(x-y)
40%
Percentage Change = Difference/Original * 100

3. HIGH: Rough est. of v2 =
1.4
Invert the second fraction (reciprocal) and multiply
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
1/x^n For example - 6-² = 1/6² = 1/36

4. How do you calculate the probability of EITHER one event OR another event happening? (Probability of A or B)
Multiply numerator times numerator and denominator times denominator.
The formula is a² + b² + c² = d² where a - b - c are the dimensions of the figure and d is the diagonal.
Probability A + Probability B
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.

5. How do you divide fractions?
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
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.
(a+b)(a-b)

6. HIGH: Area of a circle
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.
(x+y)(x-y)
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.
A=pr²

7. What'S the most important thing to remember about charts you'll see on the GRE?
The value that appears most often in a data set.
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.
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.
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'.

8. HIGH: What is the factored version of x² + 2xy + y² ?
(x+y)²
Arrangements - orders - schedules - or lists.
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions
A circle'S perimeter is roughly 3x its diameter (the formula is pd).

9. HIGH: What is the unfactored version of x²-y² ?
(x+y)(x-y)
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
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
A line is a 180-degree angle.

10. HIGH: Describe how to deal with 2 sets of parentheses.
An integer is divisible by 9 if the sum of its digits is divisible by 9.
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)+
1.7
x² -2xy + y²

11. What is a 'Right' triangle?
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.
Multiply each numerator by the other fraction'S denominator. Example: 3/7 and 7/12. Multiply 312 = 36 - and 77 = 49. If you completed the full calculation - you'd also cross-multiply the denominators - but you don'T have to in order to compare values
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.

12. How do you solve a combination?

13. What is the 'distributive law'?
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
1/1
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.

14. Area of a parallelogram?
2pr -or- pd
Bh
V=pr²h (This is just the area multiplied by the height)
Find a common denominator and make equivalent fractions. Then add or subtract.

15. Define the mode of a set of numbers.
Probability A + Probability B
1.7
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.
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. What number goes on the bottom of a probability fraction?
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions
A 90-degree angle.
The total # of possible outcomes.
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.

17. Define 'proportionate' values
1/1
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
6
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.

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

19. When 2 lines are perpendicular to each other - their intersection forms 4 angles. What degree are these 4 angles?
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.
90 degrees each.
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

20. HIGH: How do you calculate the circumference of a circle?
For RIGHT triangles only: c² = a² + b² 'c' is the length of the hypotenuse; 'a' and 'b' are the other two sides ('legs')
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
2pr -or- pd
Example: 1 < x < 10

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

22. When a pair of parallel lines is intersected by another line - two types of angles are formed. What are they?

23. HIGH: What are the percentages for standard deviation?
Multiply each numerator by the other fraction'S denominator. Example: 3/7 and 7/12. Multiply 312 = 36 - and 77 = 49. If you completed the full calculation - you'd also cross-multiply the denominators - but you don'T have to in order to compare values
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 value that appears most often in a data set.
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.

24. HIGH: Rough est. of v3 =
1.7
The formula is a² + b² + c² = d² where a - b - c are the dimensions of the figure and d is the diagonal.
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
S*v2

25. v4 =
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.
2
Find the total - or whole - first - and then set up a Ratio Box.
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.

26. HIGH: Rough est. of v1 =
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.
(x+y)(x-y)
An integer is divisible by 5 if its units digit is either 0 or 5.
1

27. What is the sum of any 'big' angle and any 'Small' angle?
Favorable Outcomes/Total Possible Outcomes
180 degrees.
The value that appears most often in a data set.
2 - 14 - and 34. So - a Bell - standard deviation - or normal distribution curve would be segmented: | 2% | 14% | 34% |average score| 34% | 14% | 2% |

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

29. How do you multiply fractions?
Multiply numerator times numerator and denominator times denominator.
Not necessarily. This is a trick question - because x could be either positive or negative.
Not reading the problems carefully enough!
1/1

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

31. Probability Formula
1
Arrangements - orders - schedules - or lists.
Favorable Outcomes/Total Possible Outcomes
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

32. An integer is divisible by 8 if...

33. Explain how to solve for 7/¼
A=pr²
This equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28
The total # of possible outcomes.
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.

34. What are 'vertical angles'?
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
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.
An integer is divisible by 8 if its last three digits form a number that'S divisible by 8. For example - 11 -640.

35. What is the formula to determine probability?
Multiply numerator times numerator and denominator times denominator.
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
1.4
A line is a 180-degree angle.

36. HIGH: How do you multiply powers with the same base?
Add the exponents - retain the base. for example - x² + x5 = x²+5 = x7
80%
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.
An integer is divisible by 9 if the sum of its digits is divisible by 9.

37. If something is possible but not certain - what is the numeric range of probability of it happening?
The average - mean - median - or mode.
Between 0 and 1.
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.
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.

38. HIGH: What is the Pythagorean theorem?

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

40. What do combination problems usually ask for?
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.
2pr -or- pd
Groups - teams - or committees.
80%

41. a² - b² is equal to
(a+b)(a-b)
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.
2 - 14 - and 34. So - a Bell - standard deviation - or normal distribution curve would be segmented: | 2% | 14% | 34% |average score| 34% | 14% | 2% |
1

42. What causes 80% of errors on the math section of the GRE?
Not reading the problems carefully enough!
An integer is divisible by 2 if its units digit is divisible by 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.
A circle'S perimeter is roughly 3x its diameter (the formula is pd).

43. An integer is divisible by 3 if...
A=pr²
An integer is divisible by 8 if its last three digits form a number that'S divisible by 8. For example - 11 -640.
The value that appears most often in a data set.
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.

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

45. What is an 'equilateral' triangle?
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.
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.
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

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

47. If x² = 144 - does v144 = x?
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%.
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
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.
Not necessarily. This is a trick question - because x could be either positive or negative.

48. Define the range of a set of numbers.
V=pr²h (This is just the area multiplied by the height)
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.
25%

49. HIGH: Volume of a cylinder?
2
V=pr²h (This is just the area multiplied by the height)
Turn the second fraction upside down (find its reciprocal) and multiply. Example: 2/3 ÷ 4/5 = 2/3 * 5/4
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

50. Solve this: v6 * -v6 = ?
A 90-degree angle.
1
6
40%