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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. An integer is divisible by 8 if...

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

3. On the GRE - should you ever assume that diagrams are truthful?
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.
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.
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.

4. Define the mode of a set of numbers.
Turn the second fraction upside down (find its reciprocal) and multiply. Example: 2/3 ÷ 4/5 = 2/3 * 5/4
(0 -0)
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 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.

5. HIGH: What is a 'Right isosceles' triangle?
2r
180 degrees
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
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.

6. Does order matter for a permutation? How about for a combination?
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.
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.
Turn the second fraction upside down (find its reciprocal) and multiply. Example: 2/3 ÷ 4/5 = 2/3 * 5/4
Order does matter for a permutation - but does not matter for a combination.

7. How many angles are formed when 2 lines intersect? and what is the sum of these angles?
4 angles are formed. Their sum is 360 degrees
(a+b)(a-b)
Groups - teams - or committees.
(x+y)(x-y)

8. 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
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.
2
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.

9. Convert to a percentage: 2/5
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3
40%
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.
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

10. What degree angle is a line?
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)+
360 degrees
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.
A line is a 180-degree angle.

11. How do you divide fractions?
Invert the second fraction (reciprocal) and multiply
A radius
40%
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.

12. HIGH: What is a '30:60:90' triangle?
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
Add the exponents - retain the base. for example - x² + x5 = x²+5 = x7
80%
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

13. HIGH: What must be true before a quadratic equation can be solved?

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

15. HIGH: What is the unfactored version of (x+y)² ?
Groups - teams - or committees.
Turn the second fraction upside down (find its reciprocal) and multiply. Example: 2/3 ÷ 4/5 = 2/3 * 5/4
x² + 2xy + y²
Find the total - or whole - first - and then set up a Ratio Box.

16. Convert to a percentage: 3/5
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.
For RIGHT triangles only: c² = a² + b² 'c' is the length of the hypotenuse; 'a' and 'b' are the other two sides ('legs')
60%
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.

17. What are 'vertical angles'?
A radius
S²
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
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.

18. HIGH: what is the side ratio for a Right Isosceles triangle?
The value that appears most often in a data set.
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
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 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.

19. HIGH: What is the median?
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
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.
The # falling in the center of an ordered data set
(0 -0)

20. a² - b² is equal to
Percentage Change = Difference/Original * 100
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.
(a+b)(a-b)
(x-y)²

21. Explain how to divide fractions.
The formula is a² + b² + c² = d² where a - b - c are the dimensions of the figure and d is the diagonal.
Turn the second fraction upside down (find its reciprocal) and multiply. Example: 2/3 ÷ 4/5 = 2/3 * 5/4
Groups - teams - or committees.
1/x^n For example - 6-² = 1/6² = 1/36

22. How do you add or subtract fractions?
Find a common denominator and make equivalent fractions. Then add or subtract.
360 degrees
1/x^n For example - 6-² = 1/6² = 1/36
90 degrees each.

23. What is the equation for a group problem?
A 90-degree angle.
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
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

24. HIGH: What is the unfactored version of (x-y)² ?
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions
Probability A + Probability B
x² -2xy + y²
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.

25. HIGH: What is the formula for the diagonal of any square?
Find a common denominator and make equivalent fractions. Then add or subtract.
S*v2
V=s³
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.

26. HIGH: Area of a circle
A 90-degree angle.
Probability A * Probability B
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
A=pr²

27. Explain how to calculate an average (arithmetic mean)
180 degrees.
S*v2
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3
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%.

28. HIGH: Simplify this: v75/v27
Find a common denominator and make equivalent fractions. Then add or subtract.
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%.
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.
360 degrees

29. If x² = 144 - does v144 = x?
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
The value that appears most often in a data set.
Invert the second fraction (reciprocal) and multiply
Not necessarily. This is a trick question - because x could be either positive or negative.

30. What is the 'distributive law'?
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
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.
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5
3:4:5 5:12:13

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

32. HIGH: How much of your times table should you know - for the GRE?
25%
It will be a great advantage on test day to have your times table memorized from 1 through 15.
80%
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.

33. HIGH: What is the mode?
The value that appears most often in a data set.
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.
A triangle in which one of the three interior angles is 90 degrees.
Not necessarily. This is a trick question - because x could be either positive or negative.

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

35. HIGH: What is the factored version of x² + 2xy + y² ?
(x+y)²
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)+
2 - 14 - and 34. So - a Bell - standard deviation - or normal distribution curve would be segmented: | 2% | 14% | 34% |average score| 34% | 14% | 2% |
A triangle in which one of the three interior angles is 90 degrees.

36. How do you multiply fractions?
Not reading the problems carefully enough!
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
x² + 2xy + y²
Multiply numerator times numerator and denominator times denominator.

37. HIGH: What are the percentages for standard deviation?
Groups - teams - or committees.
(x+y)(x-y)
2 - 14 - and 34. So - a Bell - standard deviation - or normal distribution curve would be segmented: | 2% | 14% | 34% |average score| 34% | 14% | 2% |
An integer is divisible by 9 if the sum of its digits is divisible by 9.

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

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

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

41. An integer is divisible by 5 if...
An integer is divisible by 5 if its units digit is either 0 or 5.
'Big' angles and 'Small' angles.
Not necessarily. This is a trick question - because x could be either positive or negative.
Multiply numerator times numerator and denominator times denominator.

42. What do permutation problems often ask for?
Arrangements - orders - schedules - or lists.
Probability A * Probability B
Invert the second fraction (reciprocal) and multiply
x² + 2xy + y²

43. HIGH: What is the order of math operations - and the mnemonic to remember it?
40%
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
Not reading the problems carefully enough!
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.

44. Simplify this: v32
A radius
A line is a 180-degree angle.
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.
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.

45. List two odd behaviors of exponents
Favorable Outcomes/Total 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.
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.
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

46. How is a range expressed with inequalities?
Probability A + Probability B
Not necessarily. This is a trick question - because x could be either positive or negative.
Example: 1 < x < 10
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.

47. What'S the most important thing to remember about charts you'll see on the GRE?
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
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'.
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.
Find the total - or whole - first - and then set up a Ratio Box.

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

49. Area of a square?
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
The # falling in the center of an ordered data set
S²
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.

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