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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 add or subtract fractions?
Find a common denominator and make equivalent fractions. Then add or subtract.
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
Not reading the problems carefully enough!
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. HIGH: Rough est. of v1 =
1.7
2r
1/x^n For example - 6-² = 1/6² = 1/36
1

3. a² - b² is equal to
(x-y)²
It will be a great advantage on test day to have your times table memorized from 1 through 15.
x² -2xy + y²
(a+b)(a-b)

4. HIGH: What is the unfactored version of (x+y)² ?
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
x² + 2xy + y²
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions

5. An integer is divisible by 5 if...
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
The average - mean - median - or mode.
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.
An integer is divisible by 5 if its units digit is either 0 or 5.

6. How do you divide fractions?
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
Invert the second fraction (reciprocal) and multiply
180 degrees.
Not necessarily. This is a trick question - because x could be either positive or negative.

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

8. HIGH: To divide powers with the same base...
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5
80%
Not reading the problems carefully enough!
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.

9. Define 'proportionate' values
A radius
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
V=s³
Percentage Change = Difference/Original * 100

10. HIGH: Rough est. of v3 =
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.
1
An integer is divisible by 9 if the sum of its digits is divisible by 9.
1.7

11. What degree angle is a line?
A line is a 180-degree angle.
Order does matter for a permutation - but does not matter for a combination.
1
An integer is divisible by 5 if its units digit is either 0 or 5.

12. HIGH: How do you multiply powers with the same base?
Add the exponents - retain the base. for example - x² + x5 = x²+5 = x7
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions
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.
6

13. In a coordinate system - identify the quadrants and describe their location.
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
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.
1/x^n For example - 6-² = 1/6² = 1/36
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.

14. What causes 80% of errors on the math section of the GRE?
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.
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 average - mean - median - or mode.
Not reading the problems carefully enough!

15. HIGH: x^-n is equal to
Not reading the problems carefully enough!
1.7
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/x^n For example - 6-² = 1/6² = 1/36

16. What number goes on the bottom of a probability fraction?
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
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.
The total # of possible outcomes.
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

17. Diameter of a circle?
25%
It will be a great advantage on test day to have your times table memorized from 1 through 15.
Find the total - or whole - first - and then set up a Ratio Box.
2r

18. What are the side ratios for a 30:60:90 triangle?
Order does matter for a permutation - but does not matter for a combination.
The total # of possible outcomes.
180 degrees.
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.

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

20. Does order matter for a permutation? How about for a combination?
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'.
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.
Order does matter for a permutation - but does not matter for a combination.
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

21. What is the formula to determine probability?
It will be a great advantage on test day to have your times table memorized from 1 through 15.
Between 0 and 1.
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
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

22. Probability Formula
Favorable Outcomes/Total Possible Outcomes
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.
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.

23. HIGH: What is the unfactored version of x²-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
This equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28
(0 -0)
(x+y)(x-y)

24. 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.
1.4
Percentage Change = Difference/Original * 100
Turn the second fraction upside down (find its reciprocal) and multiply. Example: 2/3 ÷ 4/5 = 2/3 * 5/4

25. v4 =
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 - and greater than the difference between the other two sides.
2
A line is a 180-degree angle.

26. How do you calculate the percentage of change?
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
Percentage Change = Difference/Original * 100
A radius
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.

27. HIGH: Volume of a cube?
V=s³
180 degrees.
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.
Bh

28. The probability of an event happening and the probability of an event NOT happening must add up to what number?
The average - mean - median - or mode.
Slope = rise/run. Find the change in y-coordinates (rise) and the change in x-coordinates (run) to calculate.
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
1. Given event A: A + notA = 1.

29. What is the 'distributive law'?
Not necessarily. This is a trick question - because x could be either positive or negative.
25%
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.
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.

30. HIGH: How do you calculate the circumference of a circle?
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.
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.
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
2pr -or- pd

31. What is an 'equilateral' triangle?
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.
4 angles are formed. Their sum is 360 degrees
S²

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

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

34. HIGH: What are the percentages for standard deviation?
(x+y)(x-y)
2 - 14 - and 34. So - a Bell - standard deviation - or normal distribution curve would be segmented: | 2% | 14% | 34% |average score| 34% | 14% | 2% |
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
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.

35. HIGH: Volume of a cylinder?
V=pr²h (This is just the area multiplied by the height)
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 8 if its last three digits form a number that'S divisible by 8. For example - 11 -640.
Between 0 and 1.

36. HIGH: What is the factored version of (x+y)(x-y) ?
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.
A circle'S perimeter is roughly 3x its diameter (the formula is pd).
x²-y²
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.

37. An integer is divisible by 9 if...
An integer is divisible by 9 if the sum of its digits is divisible by 9.
Turn the second fraction upside down (find its reciprocal) and multiply. Example: 2/3 ÷ 4/5 = 2/3 * 5/4
The total # of possible outcomes.
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.

38. Solve this: v6 * -v6 = ?
6
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
Between 0 and 1.
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'.

39. Explain how to use a 'Rate Pie'
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
Find a common denominator and make equivalent fractions. Then add or subtract.
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
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.

40. The three interior angles of a triangle add up to...
180 degrees
A 90-degree angle.
Groups - teams - or committees.
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'.

41. Convert to a percentage: 2/5
40%
Percentage Change = Difference/Original * 100
x² + 2xy + y²
(x-y)²

42. Define a factorial of a number - and how it is written.
A triangle in which one of the three interior angles is 90 degrees.
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
For RIGHT triangles only: c² = a² + b² 'c' is the length of the hypotenuse; 'a' and 'b' are the other two sides ('legs')
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.

43. Explain how to solve for 7/¼
1/x^n For example - 6-² = 1/6² = 1/36
This equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28
25%
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.

44. What is a 'Right' triangle?
(a+b)(a-b)
A triangle in which one of the three interior angles is 90 degrees.
Turn the second fraction upside down (find its reciprocal) and multiply. Example: 2/3 ÷ 4/5 = 2/3 * 5/4
Multiply numerator times numerator and denominator times denominator.

45. An integer is divisible by 2 if...
An integer is divisible by 2 if its units digit is divisible by 2.
(0 -0)
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
x² -2xy + y²

46. 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
'Big' angles and 'Small' angles.
40%
(x+y)²

47. The three exterior angles of a triangle add up to...
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.
360 degrees
S*v2
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.

48. Convert to a percentage: 4/5
80%
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
Groups - teams - or committees.
6

49. What do combination problems usually ask for?
Groups - teams - or committees.
An integer is divisible by 2 if its units digit is divisible by 2.
25%
x² + 2xy + y²

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
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.
6
An integer is divisible by 8 if its last three digits form a number that'S divisible by 8. For example - 11 -640.