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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: List the two most common side ratios for right triangles
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.
3:4:5 5:12:13
An integer is divisible by 9 if the sum of its digits is divisible by 9.
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3

2. HIGH: What is a '30:60:90' triangle?
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
It will be a great advantage on test day to have your times table memorized from 1 through 15.
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.

3. An integer is divisible by 3 if...
Not necessarily. This is a trick question - because x could be either positive or negative.
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.
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.
Find the total - or whole - first - and then set up a Ratio Box.

4. Convert to a percentage: 1/4
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'.
25%
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

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

6. What number goes on the bottom of a probability fraction?
40%
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
x² + 2xy + y²
The total # of possible outcomes.

7. What is the 'distributive law'?
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.
S*v2
A triangle in which one of the three interior angles is 90 degrees.
1.4

8. Area of a square?
x² -2xy + y²
S²
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
Arrangements - orders - schedules - or lists.

9. HIGH: How do you multiply and divide square roots?
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.
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.
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
Add the exponents - retain the base. for example - x² + x5 = x²+5 = x7

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

11. 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.
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
This equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28
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.

12. An integer is divisible by 9 if...
(x-y)²
x² + 2xy + y²
An integer is divisible by 9 if the sum of its digits is divisible by 9.
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.

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

14. HIGH: how do you calculate a diagonal inside a 3-dimensional rectangular box?
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.
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.
The formula is a² + b² + c² = d² where a - b - c are the dimensions of the figure and d is the diagonal.
A radius

15. HIGH: How do you calculate the circumference of a circle?
2pr -or- pd
A triangle in which one of the three interior angles is 90 degrees.
1.7
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.

16. How is a range expressed with inequalities?
(# of possible outcomes that satisfy the condition) ÷ (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.
80%
Example: 1 < x < 10

17. HIGH: How much of your times table should you know - for the GRE?
It will be a great advantage on test day to have your times table memorized from 1 through 15.
1/x^n For example - 6-² = 1/6² = 1/36
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
360 degrees

18. In a coordinate system - identify the quadrants and describe their location.
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
V=s³
1.4

19. What do permutation problems often ask for?
(x+y)²
40%
Arrangements - orders - schedules - or lists.
Example: 1 < x < 10

20. a² - b² is equal to
(a+b)(a-b)
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.
60%
Not necessarily. This is a trick question - because x could be either positive or negative.

21. HIGH: Simplify this: v75/v27
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.
Invert the second fraction (reciprocal) and multiply
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.
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.

22. How do you solve a permutation?
An integer is divisible by 5 if its units digit is either 0 or 5.
4 angles are formed. Their sum is 360 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 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.

23. HIGH: What is the unfactored version of (x+y)² ?
Find the total - or whole - first - and then set up a Ratio Box.
x² + 2xy + y²
Example: 1 < x < 10
x²-y²

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

25. What is the name of a line that extends from the center of a circle to the edge of a circle?
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
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
A radius
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

26. How do you solve a combination?

27. Explain how to use an 'Average Pie'
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
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.
180 degrees.

28. HIGH: Rough est. of v1 =
1
(x+y)(x-y)
60%
x² + 2xy + y²

29. If something is possible but not certain - what is the numeric range of probability of it happening?
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.
Slope = rise/run. Find the change in y-coordinates (rise) and the change in x-coordinates (run) to calculate.
A circle'S perimeter is roughly 3x its diameter (the formula is pd).
Between 0 and 1.

30. An integer is divisible by 2 if...
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 2 if its units digit is divisible by 2.
Multiply numerator times numerator and denominator times denominator.
A 90-degree angle.

31. Define a factorial of a number - and how it is written.
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions
25%
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.
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.

32. Solve this: v6 * -v6 = ?
6
A circle'S perimeter is roughly 3x its diameter (the formula is pd).
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.
x² -2xy + y²

33. HIGH: what is the side ratio for a Right Isosceles triangle?
A triangle in which one of the three interior angles is 90 degrees.
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.
1/x^n For example - 6-² = 1/6² = 1/36
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.

34. What do combination problems usually ask for?
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
1.7
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
Groups - teams - or committees.

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

36. List all the prime numbers that are less than 30:
1.4
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
A line is a 180-degree angle.

37. HIGH: What is a 'Right isosceles' triangle?
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.
Favorable Outcomes/Total Possible Outcomes
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.

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

39. HIGH: What is the Pythagorean theorem?

40. On the GRE - should you ever assume that diagrams are truthful?
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
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.
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.
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.

41. What is a 'Right' angle?
180 degrees
Order does matter for a permutation - but does not matter for a combination.
A 90-degree angle.
Multiply numerator times numerator and denominator times denominator.

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

43. HIGH: What is the mode?
Probability A * Probability B
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.
The value that appears most often in a data set.
Percentage Change = Difference/Original * 100

44. HIGH: Volume of a cube?
Multiply numerator times numerator and denominator times denominator.
Order does matter for a permutation - but does not matter for a combination.
(0 -0)
V=s³

45. What are 'vertical angles'?
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
1
Order does matter for a permutation - but does not matter for a combination.
Add the exponents - retain the base. for example - x² + x5 = x²+5 = x7

46. What is the factored version of x² -2xy + y² ?
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.
(x-y)²
The # falling in the center of an ordered data set
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.

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

48. What is the formula to determine probability?
2r
S²
The formula is a² + b² + c² = d² where a - b - c are the dimensions of the figure and d is the diagonal.
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)

49. An integer is divisible by 5 if...
An integer is divisible by 5 if its units digit is either 0 or 5.
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 total # of possible outcomes.
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.

50. Explain how to use a 'Rate 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.
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
(a+b)(a-b)
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