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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 mode?
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.
An integer is divisible by 2 if its units digit is divisible by 2.
V=pr²h (This is just the area multiplied by the height)

2. Diameter of a circle?
An integer is divisible by 9 if the sum of its digits is divisible by 9.
A radius
Order does matter for a permutation - but does not matter for a combination.
2r

3. HIGH: What is a 'Right isosceles' triangle?
Order does matter for a permutation - but does not matter for a combination.
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.
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.
Find the total - or whole - first - and then set up a Ratio Box.

4. An integer is divisible by 9 if...
An integer is divisible by 9 if the sum of its digits is divisible by 9.
The value that appears most often in a data set.
A triangle in which one of the three interior angles is 90 degrees.
An integer is divisible by 8 if its last three digits form a number that'S divisible by 8. For example - 11 -640.

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

6. HIGH: What is the median?
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 # falling in the center of an ordered data set
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.
Find a common denominator and make equivalent fractions. Then add or subtract.

7. Explain how to solve for 7/¼
(x+y)²
Multiply numerator times numerator and denominator times denominator.
(x-y)²
This equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28

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

9. What degree angle is a line?
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
For RIGHT triangles only: c² = a² + b² 'c' is the length of the hypotenuse; 'a' and 'b' are the other two sides ('legs')
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.
A line is a 180-degree angle.

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

11. What is the 'Third side' rule for triangles?
A radius
1.4
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.
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3

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

13. If something is certain to happen - how is the probability of this event expressed mathematically?
1/1
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.
1/x^n For example - 6-² = 1/6² = 1/36
25%

14. What number goes on the bottom of a probability fraction?
2r
The total # of possible outcomes.
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.
90 degrees each.

15. How do you calculate the probability of two events in a row? (Probability of A and B)
A triangle in which one of the three interior angles is 90 degrees.
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.
Multiply numerator times numerator and denominator times denominator.
Probability A * Probability B

16. HIGH: x^-n is equal to
Probability A + Probability B
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)+
Order does matter for a permutation - but does not matter for a combination.
1/x^n For example - 6-² = 1/6² = 1/36

17. HIGH: Area of a triangle?
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.
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.
Add the exponents - retain the base. for example - x² + x5 = x²+5 = x7

18. In a coordinate system - what is the origin?
Invert the second fraction (reciprocal) and multiply
Slope = rise/run. Find the change in y-coordinates (rise) and the change in x-coordinates (run) to calculate.
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.
(0 -0)

19. HIGH: Define the formula for calculating slope.
Multiply numerator times numerator and denominator times denominator.
360 degrees
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
Slope = rise/run. Find the change in y-coordinates (rise) and the change in x-coordinates (run) to calculate.

20. HIGH: How do you calculate the circumference of a circle?
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
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.
180 degrees.
2pr -or- pd

21. What is the 'distributive law'?
6
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.
x² + 2xy + y²
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)

22. HIGH: Rough est. of v3 =
80%
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%.
1.7
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.

23. How do you solve a permutation?
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
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
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
(x+y)²

24. An integer is divisible by 5 if...
25%
The # falling in the center of an ordered data set
An integer is divisible by 5 if its units digit is either 0 or 5.
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%.

25. HIGH: What are the percentages for standard deviation?
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.
40%
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions
2 - 14 - and 34. So - a Bell - standard deviation - or normal distribution curve would be segmented: | 2% | 14% | 34% |average score| 34% | 14% | 2% |

26. What kind of triangle is this: has two sides of equal length - and a 90 degree angle?
80%
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.
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.
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.

27. What is a 'Right' triangle?
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
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 formula is a² + b² + c² = d² where a - b - c are the dimensions of the figure and d is the diagonal.
A triangle in which one of the three interior angles is 90 degrees.

28. If x² = 144 - does v144 = x?
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.
Example: 1 < x < 10
(x-y)²
Not necessarily. This is a trick question - because x could be either positive or negative.

29. Define 'proportionate' values
Invert the second fraction (reciprocal) and multiply
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
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.
The value that appears most often in a data set.

30. HIGH: Volume of a cylinder?
Percentage Change = Difference/Original * 100
Favorable Outcomes/Total Possible Outcomes
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
V=pr²h (This is just the area multiplied by the height)

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

32. How do you calculate the probability of EITHER one event OR another event happening? (Probability of A or B)
A triangle in which one of the three interior angles is 90 degrees.
Probability A + Probability B
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.
3:4:5 5:12:13

33. 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
Arrangements - orders - schedules - or lists.
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
A line is a 180-degree angle.

34. How many degrees does a circle contain?
Between 0 and 1.
A circle'S perimeter is roughly 3x its diameter (the formula is pd).
360 degrees
A 90-degree angle.

35. The three exterior angles of a triangle add up to...
40%
360 degrees
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
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.

36. What is the sum of any 'big' angle and any 'Small' angle?
80%
4 angles are formed. Their sum is 360 degrees
x² -2xy + y²
180 degrees.

37. How do you divide fractions?
(0 -0)
Invert the second fraction (reciprocal) and multiply
x²-y²
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.

38. In a coordinate system - identify the quadrants and describe their location.
60%
360 degrees
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.

39. Explain the difference between handling a permutation versus a combination.
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.
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
Order does matter for a permutation - but does not matter for a combination.
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.

40. HIGH: How do you get rid of the fraction in this equation: 5x + 3/2 = 7x
25%
Find the total - or whole - first - and then set up a Ratio Box.
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.
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.

41. How many angles are formed when 2 lines intersect? and what is the sum of these angles?
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.
4 angles are formed. Their sum is 360 degrees
It will be a great advantage on test day to have your times table memorized from 1 through 15.
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.

42. What is the name of a line that extends from the center of a circle to the edge of a circle?
(0 -0)
A radius
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.

43. When 2 lines are perpendicular to each other - their intersection forms 4 angles. What degree are these 4 angles?
90 degrees each.
An integer is divisible by 9 if the sum of its digits is divisible by 9.
Groups - teams - or committees.
1. Given event A: A + notA = 1.

44. What is one misleading characteristic of quadratic equations that will be exploited on the GRE?
It will be a great advantage on test day to have your times table memorized from 1 through 15.
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. 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
Arrangements - orders - schedules - or lists.

45. HIGH: how do you calculate the surface area of a rectangular box?
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
2 - 14 - and 34. So - a Bell - standard deviation - or normal distribution curve would be segmented: | 2% | 14% | 34% |average score| 34% | 14% | 2% |
1/1
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.

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

47. What is the formula to determine probability?
The value that appears most often in a data set.
Not reading the problems carefully enough!
(# of possible outcomes that satisfy the condition) ÷ (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.

48. HIGH: List the two most common side ratios for right triangles
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 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.
3:4:5 5:12:13
The total # of possible outcomes.

49. How is a range expressed with inequalities?
Example: 1 < x < 10
Probability A * Probability B
180 degrees
180 degrees.

50. Convert to a percentage: 1/4
25%
1. Given event A: A + notA = 1.
For RIGHT triangles only: c² = a² + b² 'c' is the length of the hypotenuse; 'a' and 'b' are the other two sides ('legs')
2 - 14 - and 34. So - a Bell - standard deviation - or normal distribution curve would be segmented: | 2% | 14% | 34% |average score| 34% | 14% | 2% |