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GRE High Frequency Math Terms

Subjects : gre, math

Instructions:

Answer 50 questions in 15 minutes.
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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. What is the name of a line that extends from the center of a circle to the edge of a circle?
A radius
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
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.
(x+y)(x-y)

2. If something is certain to happen - how is the probability of this event expressed mathematically?
The formula is a² + b² + c² = d² where a - b - c are the dimensions of the figure and d is the diagonal.
(0 -0)
1.4
1/1

3. HIGH: What is a '30:60:90' triangle?
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
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.
Slope = rise/run. Find the change in y-coordinates (rise) and the change in x-coordinates (run) to calculate.
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

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

5. Convert to a percentage: 2/5
Favorable Outcomes/Total Possible Outcomes
1/1
Find a common denominator and make equivalent fractions. Then add or subtract.
40%

6. What is the 'distributive law'?
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 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.
2pr -or- pd
Invert the second fraction (reciprocal) and multiply

7. HIGH: What is the Pythagorean theorem?

8. HIGH: What is the mode?
x² + 2xy + y²
The # falling in the center of an ordered data set
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.
The value that appears most often in a data set.

9. Explain how to divide fractions.
(x+y)²
(x-y)²
A 90-degree angle.
Turn the second fraction upside down (find its reciprocal) and multiply. Example: 2/3 ÷ 4/5 = 2/3 * 5/4

10. Explain how to use an 'Average Pie'
Invert the second fraction (reciprocal) and multiply
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.
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.

11. HIGH: how do you calculate the surface area of a rectangular box?
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 8 if its last three digits form a number that'S divisible by 8. For example - 11 -640.
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
Not reading the problems carefully enough!

12. In a coordinate system - identify the quadrants and describe their location.
x² -2xy + y²
1/1
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.

13. HIGH: Rough est. of v1 =
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.
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.
1
The value that appears most often in a data set.

14. Simplify this: v32
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
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 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.
Arrangements - orders - schedules - or lists.

15. HIGH: What is the unfactored version of (x-y)² ?
x² -2xy + y²
Percentage Change = Difference/Original * 100
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3
(x+y)²

16. Convert to a percentage: 1/4
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.
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5
25%
x²-y²

17. HIGH: What numbers does ETS hope you'll forget to consider - for quant comp questions?
Percentage Change = Difference/Original * 100
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions
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
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.

18. What is the key to dealing with ratio questions?
Find the total - or whole - first - and then set up a Ratio Box.
An integer is divisible by 2 if its units digit is divisible by 2.
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.
An integer is divisible by 9 if the sum of its digits is divisible by 9.

19. How do you solve a permutation?
3:4:5 5:12:13
Find a common denominator and make equivalent fractions. Then add or subtract.
The formula is a² + b² + c² = d² where a - b - c are the dimensions of the figure and d is the diagonal.
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

20. HIGH: What is the unfactored version of x²-y² ?
A circle'S perimeter is roughly 3x its diameter (the formula is pd).
(x+y)(x-y)
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 ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.

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

22. HIGH: Describe and define three expressions of quadratic equations - in both factored and unfactored forms. Know these cold.
A=pr²
25%
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3
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

23. The three interior angles of a triangle add up to...
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
The average - mean - median - or mode.
2
180 degrees

24. How many degrees does a circle contain?
360 degrees
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
80%
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.

25. HIGH: How much of your times table should you know - for the GRE?
Multiply numerator times numerator and denominator times denominator.
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.
For RIGHT triangles only: c² = a² + b² 'c' is the length of the hypotenuse; 'a' and 'b' are the other two sides ('legs')
It will be a great advantage on test day to have your times table memorized from 1 through 15.

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

27. Convert to a percentage: 4/5
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
6
80%
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.

28. HIGH: Volume of a cylinder?
A circle'S perimeter is roughly 3x its diameter (the formula is pd).
V=pr²h (This is just the area multiplied by the height)
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.
For RIGHT triangles only: c² = a² + b² 'c' is the length of the hypotenuse; 'a' and 'b' are the other two sides ('legs')

29. 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
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
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.
Find a common denominator and make equivalent fractions. Then add or subtract.

30. An integer is divisible by 9 if...
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
1.7
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.
An integer is divisible by 9 if the sum of its digits is divisible by 9.

31. What is the equation for a group problem?
Probability A * Probability B
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
x² + 2xy + y²
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'.

32. An integer is divisible by 3 if...
2 - 14 - and 34. So - a Bell - standard deviation - or normal distribution curve would be segmented: | 2% | 14% | 34% |average score| 34% | 14% | 2% |
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
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.
Order does matter for a permutation - but does not matter for a combination.

33. Does order matter for a permutation? How about for a combination?
Order does matter for a permutation - but does not matter for a combination.
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.
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.
Find a common denominator and make equivalent fractions. Then add or subtract.

34. What is a 'Right' angle?
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 integer is divisible by 9 if the sum of its digits is divisible by 9.
3:4:5 5:12:13

35. How do you calculate the percentage of change?
An integer is divisible by 8 if its last three digits form a number that'S divisible by 8. For example - 11 -640.
Invert the second fraction (reciprocal) and multiply
Percentage Change = Difference/Original * 100
Between 0 and 1.

36. 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.
Slope = rise/run. Find the change in y-coordinates (rise) and the change in x-coordinates (run) to calculate.
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.

37. The three exterior angles of a triangle add up to...
3:4:5 5:12:13
The formula is a² + b² + c² = d² where a - b - c are the dimensions of the figure and d is the diagonal.
V=pr²h (This is just the area multiplied by the height)
360 degrees

38. On the GRE - should you ever assume that diagrams are truthful?
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.
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
Probability A + Probability B
1.7

39. Define the mode of a set of numbers.
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
'Big' angles and 'Small' angles.
Invert the second fraction (reciprocal) and multiply
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.

40. Area of a parallelogram?
360 degrees
4 angles are formed. Their sum is 360 degrees
x²-y²
Bh

41. What is the sum of any 'big' angle and any 'Small' angle?
A=pr²
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
180 degrees.
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

42. What is an 'equilateral' triangle?
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.
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.
80%
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.

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

44. a² - b² is equal to
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.
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions
1
(a+b)(a-b)

45. HIGH: Rough est. of v2 =
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
A line is a 180-degree angle.
The # falling in the center of an ordered data set
1.4

46. How do you calculate the probability of EITHER one event OR another event happening? (Probability of A or B)
Arrangements - orders - schedules - or lists.
360 degrees
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.
Probability A + Probability B

47. The probability of an event happening and the probability of an event NOT happening must add up to what number?
1. Given event A: A + notA = 1.
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
The total # of possible outcomes.
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.

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

49. HIGH: Area of a triangle?
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.
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
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 9 if the sum of its digits is divisible by 9.

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