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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. How do you calculate the probability of EITHER one event OR another event happening? (Probability of A or B)
Probability A + Probability B
A=pr²
(a+b)(a-b)
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.

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

3. What is the sum of any 'big' angle and any 'Small' angle?
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
180 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.
60%

4. HIGH: Rough est. of v1 =
A=pr²
1
(0 -0)
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.

5. HIGH: what is the side ratio for a Right Isosceles triangle?
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
A radius
The ratio of sides is x:x:xv2 - where xv2 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.

6. HIGH: how do you calculate the surface area of a rectangular box?
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.
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
2r
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.

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

8. What kind of triangle is this: has two sides of equal length - and a 90 degree angle?
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.
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.
Arrangements - orders - schedules - or lists.
'Big' angles and 'Small' angles.

9. Explain how to use a 'Rate Pie'
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
S*v2
S²
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.

10. Diameter of a circle?
(x-y)²
Probability A + Probability B
2r
Order does matter for a permutation - but does not matter for a combination.

11. An integer is divisible by 2 if...
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 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.
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 2 if its units digit is divisible by 2.

12. HIGH: To divide powers with the same base...
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
3:4:5 5:12:13
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.

13. HIGH: Explain the process to solve '56 is what percent of 80?'

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

15. HIGH: How do you get rid of the fraction in this equation: 5x + 3/2 = 7x
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.
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.
(x-y)²
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.

16. HIGH: What numbers does ETS hope you'll forget to consider - for quant comp questions?
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.
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions
A 90-degree angle.
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3

17. Convert to a percentage: 2/5
The # falling in the center of an ordered data set
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.
40%
1.4

18. What is the equation for a group problem?
Between 0 and 1.
V=s³
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
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.

19. HIGH: Rough est. of v2 =
80%
x² + 2xy + y²
1.4
Probability A + Probability B

20. Convert to a percentage: 1/4
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.
80%
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.
25%

21. What is the 'Third side' rule for triangles?
Find a common denominator and make equivalent fractions. Then add or subtract.
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 8 if its last three digits form a number that'S divisible by 8. For example - 11 -640.
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions

22. What is the factored version of x² -2xy + y² ?
(x-y)²
Invert the second fraction (reciprocal) and multiply
V=s³
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.

23. HIGH: What is the side ratio for a 30:60:90 triangle?
An integer is divisible by 5 if its units digit is either 0 or 5.
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
1/1
It will be a great advantage on test day to have your times table memorized from 1 through 15.

24. HIGH: How do you multiply and divide square roots?
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
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
A circle'S perimeter is roughly 3x its diameter (the formula is pd).

25. What is the key to dealing with ratio questions?
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3
Find a common denominator and make equivalent fractions. Then add or subtract.
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
Find the total - or whole - first - and then set up a Ratio Box.

26. List all the prime numbers that are less than 30:
A circle'S perimeter is roughly 3x its diameter (the formula is pd).
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
2r
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.

27. HIGH: Volume of a cylinder?
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.
(x+y)²
3:4:5 5:12:13
V=pr²h (This is just the area multiplied by the height)

28. How do you divide fractions?
Invert the second fraction (reciprocal) and multiply
60%
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.
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.

29. What is a 'Right' triangle?
Slope = rise/run. Find the change in y-coordinates (rise) and the change in x-coordinates (run) to calculate.
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.
A triangle in which one of the three interior angles is 90 degrees.
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.

30. HIGH: What is the order of math operations - and the mnemonic to remember it?
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
Turn the second fraction upside down (find its reciprocal) and multiply. Example: 2/3 ÷ 4/5 = 2/3 * 5/4
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.
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

31. HIGH: What is the factored version of (x+y)(x-y) ?
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
x²-y²
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

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

33. The three interior angles of a triangle add up to...
6
180 degrees
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.
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.

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

35. What are 'vertical angles'?
4 angles are formed. Their sum is 360 degrees
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
Favorable Outcomes/Total Possible Outcomes
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.

36. HIGH: What is the unfactored version of (x-y)² ?
2r
x² -2xy + y²
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.
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.

37. An integer is divisible by 9 if...
An integer is divisible by 5 if its units digit is either 0 or 5.
Turn the second fraction upside down (find its reciprocal) and multiply. Example: 2/3 ÷ 4/5 = 2/3 * 5/4
4 angles are formed. Their sum is 360 degrees
An integer is divisible by 9 if the sum of its digits is divisible by 9.

38. 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.
S²
V=pr²h (This is just the area multiplied by the height)
Slope = rise/run. Find the change in y-coordinates (rise) and the change in x-coordinates (run) to calculate.

39. HIGH: Describe how to deal with 2 sets of parentheses.
Order does matter for a permutation - but does not matter for a combination.
4 angles are formed. Their sum is 360 degrees
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)+
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.

40. What is an 'equilateral' triangle?
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
1/1
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.
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%.

41. Convert to a percentage: 4/5
2
80%
A radius
Slope = rise/run. Find the change in y-coordinates (rise) and the change in x-coordinates (run) to calculate.

42. Explain how to solve for 7/¼
This equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5
Bh
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.

43. If x² = 144 - does v144 = x?
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
V=s³
(x-y)²
Not necessarily. This is a trick question - because x could be either positive or negative.

44. 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.
The total # of possible outcomes.
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
Not reading the problems carefully enough!

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

46. How many angles are formed when 2 lines intersect? and what is the sum of these angles?
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.
4 angles are formed. Their sum is 360 degrees
180 degrees.
40%

47. 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.
180 degrees.
4 angles are formed. Their sum is 360 degrees
1

48. HIGH: What is the factored version of x² + 2xy + y² ?
1.7
Add the exponents - retain the base. for example - x² + x5 = x²+5 = x7
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.
(x+y)²

49. What degree angle is a line?
Favorable Outcomes/Total Possible Outcomes
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3
A line is a 180-degree angle.

50. Explain the difference between handling a permutation versus a combination.
Groups - teams - or committees.
A 90-degree angle.
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.
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.