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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
An integer is divisible by 8 if its last three digits form a number that'S divisible by 8. For example - 11 -640.
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
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
3:4:5 5:12:13

2. Simplify this: v32
The total # of possible outcomes.
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.
6
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.

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

4. What'S the most important thing to remember about charts you'll see on the GRE?
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.
2pr -or- pd
This equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28
Multiply numerator times numerator and denominator times denominator.

5. Probability Formula
V=pr²h (This is just the area multiplied by the height)
Favorable Outcomes/Total Possible Outcomes
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.
4 angles are formed. Their sum is 360 degrees

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

7. Define 'proportionate' values
A 90-degree angle.
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
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.

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

9. How do you calculate the percentage of change?
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 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.
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.
Percentage Change = Difference/Original * 100

10. How do you multiply fractions?
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.
An integer is divisible by 9 if the sum of its digits is divisible by 9.
60%
Multiply numerator times numerator and denominator times denominator.

11. Explain the difference between handling a permutation versus a combination.
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.
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.
1.7
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

12. An integer is divisible by 5 if...
360 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.
An integer is divisible by 5 if its units digit is either 0 or 5.
Slope = rise/run. Find the change in y-coordinates (rise) and the change in x-coordinates (run) to calculate.

13. What is the equation for a group problem?
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.
An integer is divisible by 9 if the sum of its digits is divisible by 9.
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 90-degree angle.

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

15. List all the prime numbers that are less than 30:
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
60%
Favorable Outcomes/Total Possible Outcomes
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5

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

17. HIGH: Volume of a cube?
V=s³
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
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.
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

18. HIGH: How do you multiply and divide square roots?
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.
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.
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
3:4:5 5:12:13

19. Explain how to use a 'Rate Pie'
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions
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
Example: 1 < x < 10
Order does matter for a permutation - but does not matter for a combination.

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

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

22. What do permutation problems often ask for?
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
6
80%
Arrangements - orders - schedules - or lists.

23. HIGH: What is a 'Right isosceles' triangle?
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.
For RIGHT triangles only: c² = a² + b² 'c' is the length of the hypotenuse; 'a' and 'b' are the other two sides ('legs')
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.
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.

24. HIGH: Rough est. of v2 =
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'.
1.4
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. 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.

25. HIGH: How much of your times table should you know - for the GRE?
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
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.
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.

26. How do you calculate the probability of EITHER one event OR another event happening? (Probability of A or B)
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
Probability A + Probability B
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
Percentage Change = Difference/Original * 100

27. HIGH: Rough est. of v1 =
1
A radius
Not reading the problems carefully enough!
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2

28. For a bell curve - what three terms might be used to describe the number in the middle?
(a+b)(a-b)
The average - mean - median - or mode.
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.
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.

29. 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.
1/1
A line is a 180-degree angle.
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.

30. HIGH: Rough est. of v3 =
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.
Probability A * Probability B
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.

31. What is the 'distributive law'?
1.4
Example: 1 < x < 10
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

32. What is an 'equilateral' triangle?
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.
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.
1.4

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

34. How many degrees does a circle contain?
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
360 degrees
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.
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'.

35. Explain how to use an 'Average Pie'
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.
25%
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

36. What is a 'Right' angle?
A 90-degree angle.
(x+y)²
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
1.7

37. An integer is divisible by 3 if...
A=pr²
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3
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.
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.

38. Define a factorial of a number - and how it is written.
Example: 1 < x < 10
x²-y²
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 triangle in which one of the three interior angles is 90 degrees.

39. How do you divide fractions?
Invert the second fraction (reciprocal) and multiply
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
A 90-degree angle.
x² -2xy + y²

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

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

42. Does order matter for a permutation? How about for a combination?
V=pr²h (This is just the area multiplied by the height)
Order does matter for a permutation - but does not matter for a combination.
Multiply numerator times numerator and denominator times denominator.
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.

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

44. Area of a parallelogram?
(x+y)²
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
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.
Bh

45. An integer is divisible by 9 if...
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
An integer is divisible by 9 if the sum of its digits is divisible by 9.
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

46. What causes 80% of errors on the math section of the GRE?
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.
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.
Not reading the problems carefully enough!
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.

47. What is the name of a line that extends from the center of a circle to the edge of a circle?
A radius
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
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
1/1

48. When 2 lines are perpendicular to each other - their intersection forms 4 angles. What degree are these 4 angles?
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.
90 degrees each.
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
The # falling in the center of an ordered data set

49. a² - b² is equal to
Arrangements - orders - schedules - or lists.
Groups - teams - or committees.
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
(a+b)(a-b)

50. HIGH: What is the formula for the diagonal of any square?
Turn the second fraction upside down (find its reciprocal) and multiply. Example: 2/3 ÷ 4/5 = 2/3 * 5/4
x² -2xy + y²
(x+y)(x-y)
S*v2