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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 a 'Right isosceles' triangle?
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
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.
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.
It will be a great advantage on test day to have your times table memorized from 1 through 15.

2. An integer is divisible by 3 if...
S*v2
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.
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
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. Convert to a percentage: 4/5
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
80%
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.

4. 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
(x+y)(x-y)
(a+b)(a-b)
(x-y)²

5. The probability of an event happening and the probability of an event NOT happening must add up to what number?
An integer is divisible by 9 if the sum of its digits is divisible by 9.
V=pr²h (This is just the area multiplied by the height)
Favorable Outcomes/Total Possible Outcomes
1. Given event A: A + notA = 1.

6. What is a 'Right' triangle?
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5
Groups - teams - or committees.
A triangle in which one of the three interior angles is 90 degrees.
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.

7. If x² = 144 - does v144 = x?
An integer is divisible by 8 if its last three digits form a number that'S divisible by 8. For example - 11 -640.
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.
Not necessarily. This is a trick question - because x could be either positive or negative.
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.

8. Simplify this: v32
An integer is divisible by 9 if the sum of its digits is divisible by 9.
A triangle in which one of the three interior angles is 90 degrees.
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.
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

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

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

11. What are 'vertical angles'?
60%
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
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
Invert the second fraction (reciprocal) and multiply

12. For a bell curve - what three terms might be used to describe the number in the middle?
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
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.
2pr -or- pd
The average - mean - median - or mode.

13. Convert to a percentage: 2/5
For RIGHT triangles only: c² = a² + b² 'c' is the length of the hypotenuse; 'a' and 'b' are the other two sides ('legs')
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.
40%

14. How do you calculate the probability of two events in a row? (Probability of A and B)
Probability A * Probability B
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.
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.
(0 -0)

15. HIGH: x^-n is equal to
The average - mean - median - or mode.
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.
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.
1/x^n For example - 6-² = 1/6² = 1/36

16. Convert to a percentage: 1/4
25%
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.
3:4:5 5:12:13
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'.

17. Diameter of a circle?
2r
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.
4 angles are formed. Their sum is 360 degrees
'Big' angles and 'Small' angles.

18. HIGH: Area of a circle
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.
A=pr²
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
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

19. HIGH: How do you calculate the circumference of a circle?
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
2
2pr -or- pd
An integer is divisible by 9 if the sum of its digits is divisible by 9.

20. What are the side ratios for a 30:60:90 triangle?
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
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
For RIGHT triangles only: c² = a² + b² 'c' is the length of the hypotenuse; 'a' and 'b' are the other two sides ('legs')
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.

21. Explain how to use a 'Rate Pie'
A circle'S perimeter is roughly 3x its diameter (the formula is pd).
Find the total - or whole - first - and then set up a Ratio Box.
The value that appears most often in a data set.
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

22. Explain how to calculate an average (arithmetic mean)
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3
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'.
It will be a great advantage on test day to have your times table memorized from 1 through 15.
(x+y)²

23. HIGH: How do you multiply and divide square roots?
An integer is divisible by 8 if its last three digits form a number that'S divisible by 8. For example - 11 -640.
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
1/x^n For example - 6-² = 1/6² = 1/36
4 angles are formed. Their sum is 360 degrees

24. The three exterior angles of a triangle add up to...
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.
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
360 degrees

25. An integer is divisible by 2 if...
An integer is divisible by 2 if its units digit is divisible by 2.
A triangle in which one of the three interior angles is 90 degrees.
The value that appears most often in a data set.
4 angles are formed. Their sum is 360 degrees

26. HIGH: What is the mode?
Probability A + Probability B
Not reading the problems carefully enough!
The value that appears most often in a data set.
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.

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

28. How do you calculate the percentage of change?
1.7
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.
Percentage Change = Difference/Original * 100
1/x^n For example - 6-² = 1/6² = 1/36

29. How do you solve a combination?

30. a² - b² is equal to
Groups - teams - or committees.
1/1
90 degrees each.
(a+b)(a-b)

31. What is the formula to determine probability?
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
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.
1
Invert the second fraction (reciprocal) and multiply

32. In a coordinate system - what is the origin?
180 degrees
Arrangements - orders - schedules - or lists.
(0 -0)
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.

33. What is the 'distributive law'?
A circle'S perimeter is roughly 3x its diameter (the formula is pd).
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
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(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.

34. HIGH: How do you multiply powers with the same base?
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions
1.4
Add the exponents - retain the base. for example - x² + x5 = x²+5 = x7
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.

35. Define 'proportionate' values
x² -2xy + y²
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.
Arrangements - orders - schedules - or lists.
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.

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

37. HIGH: How do you get rid of the fraction in this equation: 5x + 3/2 = 7x
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
The total # of possible outcomes.
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.
An integer is divisible by 9 if the sum of its digits is divisible by 9.

38. HIGH: Describe and define three expressions of quadratic equations - in both factored and unfactored forms. Know these cold.
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
Arrangements - orders - schedules - or lists.
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
Example: 1 < x < 10

39. v4 =
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
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
2
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.

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

41. HIGH: What is the unfactored version of (x-y)² ?
60%
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
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.
x² -2xy + y²

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

43. What degree angle is a line?
A line is a 180-degree angle.
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 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. 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

44. An integer is divisible by 9 if...
The # falling in the center of an ordered data set
An integer is divisible by 9 if the sum of its digits is divisible by 9.
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 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.

45. How do you add or subtract fractions?
Find a common denominator and make equivalent fractions. Then add or subtract.
80%
Order does matter for a permutation - but does not matter for a combination.
An integer is divisible by 8 if its last three digits form a number that'S divisible by 8. For example - 11 -640.

46. HIGH: Area of a 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.
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
(x-y)²
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. HIGH: What must be true before a quadratic equation can be solved?

48. Define the range of a set of numbers.
Favorable Outcomes/Total 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.
Percentage Change = Difference/Original * 100
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.

49. HIGH: What is the order of math operations - and the mnemonic to remember it?
Bh
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.
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
(x-y)²

50. What is the key to dealing with ratio questions?
Find the total - or whole - first - and then set up a Ratio Box.
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 value that appears most often in a data set.
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.