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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. An integer is divisible by 4 if...

2. What causes 80% of errors on the math section of the GRE?
Bh
Not reading the problems carefully enough!
An integer is divisible by 9 if the sum of its digits is divisible by 9.
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.

3. Convert to a percentage: 2/5
Example: 1 < x < 10
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'.
40%
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

4. How do you divide fractions?
(0 -0)
x²-y²
Invert the second fraction (reciprocal) and multiply
This equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28

5. HIGH: How do you calculate the circumference of a circle?
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.
2pr -or- pd
A=pr²
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.

6. How do you add or subtract fractions?
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions
Find a common denominator and make equivalent fractions. Then add or subtract.

7. On the GRE - should you ever assume that diagrams are truthful?
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
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.
Groups - teams - or committees.

8. What is a 'Right' angle?
Multiply numerator times numerator and denominator times denominator.
A 90-degree angle.
6
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

9. The three exterior angles of a triangle add up to...
Invert the second fraction (reciprocal) and multiply
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.
360 degrees
2

10. Explain how to use an 'Average Pie'
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.
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.
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.
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.

11. HIGH: What is the side ratio for a 30:60:90 triangle?
Bh
90 degrees each.
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.

12. How do you multiply fractions?
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.
1.7
Between 0 and 1.
Multiply numerator times numerator and denominator times denominator.

13. What number goes on the bottom of a probability fraction?
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.
1.4
180 degrees

14. Diameter of a circle?
2r
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.
180 degrees.
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.

15. In a coordinate system - what is the origin?
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
(0 -0)
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.
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.

16. Explain the special properties of zero.
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.
'Big' angles and 'Small' angles.
6
2r

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

18. HIGH: Volume of a cylinder?
Probability A * Probability B
(a+b)(a-b)
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3
V=pr²h (This is just the area multiplied by the height)

19. Define a factorial of a number - and how it is written.
Between 0 and 1.
1.4
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.

20. How do you solve a permutation?
Example: 1 < x < 10
x² -2xy + y²
S²
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

21. When 2 lines are perpendicular to each other - their intersection forms 4 angles. What degree are these 4 angles?
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
90 degrees each.
This equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28
40%

22. HIGH: Rough est. of v2 =
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.
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
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.
1.4

23. HIGH: Rough est. of v1 =
1
1.7
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3
6

24. HIGH: Area of a triangle?
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. Given event A: A + notA = 1.
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.

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

26. HIGH: Simplify this: v75/v27
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.
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.
80%
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.

27. The three interior angles of a triangle add up to...
An integer is divisible by 2 if its units digit is divisible by 2.
180 degrees
1.7
Example: 1 < x < 10

28. 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.
Not necessarily. This is a trick question - because x could be either positive or negative.
Turn the second fraction upside down (find its reciprocal) and multiply. Example: 2/3 ÷ 4/5 = 2/3 * 5/4
1/x^n For example - 6-² = 1/6² = 1/36

29. If something is certain to happen - how is the probability of this event expressed mathematically?
1/1
A 90-degree angle.
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.
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.

30. An integer is divisible by 2 if...
An integer is divisible by 2 if its units digit is divisible by 2.
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
60%
2 - 14 - and 34. So - a Bell - standard deviation - or normal distribution curve would be segmented: | 2% | 14% | 34% |average score| 34% | 14% | 2% |

31. Define 'proportionate' values
Invert the second fraction (reciprocal) and multiply
60%
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.

32. What is the factored version of x² -2xy + y² ?
(x-y)²
1.4
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
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.

33. HIGH: Define the formula for calculating slope.
An integer is divisible by 9 if the sum of its digits is divisible by 9.
1/1
25%
Slope = rise/run. Find the change in y-coordinates (rise) and the change in x-coordinates (run) to calculate.

34. Convert to a percentage: 4/5
80%
Find the total - or whole - first - and then set up a Ratio Box.
1
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.

35. Convert to a percentage: 1/4
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3
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.
(x+y)(x-y)
25%

36. HIGH: What is the order of math operations - and the mnemonic to remember it?
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.
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
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
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.

37. If x² = 144 - does v144 = x?
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.
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
Not necessarily. This is a trick question - because x could be either positive or negative.

38. Probability Formula
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
An integer is divisible by 2 if its units digit is divisible by 2.
Invert the second fraction (reciprocal) and multiply
Favorable Outcomes/Total Possible Outcomes

39. Area of a parallelogram?
Bh
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.
Favorable Outcomes/Total Possible Outcomes
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.

40. HIGH: What is 'absolute value' - and how is it represented?

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

42. How do you calculate the probability of EITHER one event OR another event happening? (Probability of A or 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.
Probability A + Probability B
Slope = rise/run. Find the change in y-coordinates (rise) and the change in x-coordinates (run) to calculate.
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.

43. Convert to a percentage: 3/5
360 degrees
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.
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
60%

44. HIGH: List the two most common side ratios for right triangles
Find a common denominator and make equivalent fractions. Then add or subtract.
360 degrees
3:4:5 5:12:13
Groups - teams - or committees.

45. HIGH: Rough est. of v3 =
Favorable Outcomes/Total Possible Outcomes
(0 -0)
Find the total - or whole - first - and then set up a Ratio Box.
1.7

46. An integer is divisible by 3 if...
Find the total - or whole - first - and then set up a Ratio Box.
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
40%
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.

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

48. Explain how to divide fractions.
Turn the second fraction upside down (find its reciprocal) and multiply. Example: 2/3 ÷ 4/5 = 2/3 * 5/4
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.
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.
Add the exponents - retain the base. for example - x² + x5 = x²+5 = x7

49. What is the 'Third side' rule for triangles?
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 line is a 180-degree angle.
(x+y)(x-y)
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.

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