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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. What is one misleading characteristic of quadratic equations that will be exploited on the GRE?
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.
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.
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.

2. v4 =
The # falling in the center of an ordered data set
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
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%.

3. HIGH: what is the side ratio for a Right Isosceles triangle?
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.
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
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.

4. HIGH: What is the Pythagorean theorem?

5. What is the sum of any 'big' angle and any 'Small' angle?
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
(a+b)(a-b)
1.7
180 degrees.

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

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

8. HIGH: Volume of a cube?
V=s³
3:4:5 5:12:13
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.
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.

9. HIGH: List the two most common side ratios for right triangles
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.
Groups - teams - or committees.
3:4:5 5:12:13
An integer is divisible by 2 if its units digit is divisible by 2.

10. What kind of triangle is this: has two sides of equal length - and a 90 degree angle?
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.
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. Given event A: A + notA = 1.
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.

11. HIGH: Rough est. of v3 =
1.7
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
Invert the second fraction (reciprocal) and multiply
V=pr²h (This is just the area multiplied by the height)

12. HIGH: What is the unfactored version of x²-y² ?
V=pr²h (This is just the area multiplied by the height)
(x+y)(x-y)
A triangle in which one of the three interior angles is 90 degrees.
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.

13. 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
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
(0 -0)
It will be a great advantage on test day to have your times table memorized from 1 through 15.

14. How do you multiply fractions?
A=pr²
Find the total - or whole - first - and then set up a Ratio Box.
2r
Multiply numerator times numerator and denominator times denominator.

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

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

17. HIGH: What is a 'Right isosceles' triangle?
1/x^n For example - 6-² = 1/6² = 1/36
The total # of possible outcomes.
Favorable Outcomes/Total Possible Outcomes
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.

18. 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.
60%
1/x^n For example - 6-² = 1/6² = 1/36
The # falling in the center of an ordered data set

19. HIGH: What is the order of math operations - and the mnemonic to remember it?
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
1.7
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'.

20. Solve this: v6 * -v6 = ?
A circle'S perimeter is roughly 3x its diameter (the formula is pd).
S*v2
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.
6

21. HIGH: How do you multiply powers with the same base?
Multiply numerator times numerator and denominator times denominator.
Add the exponents - retain the base. for example - x² + x5 = x²+5 = x7
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.
It will be a great advantage on test day to have your times table memorized from 1 through 15.

22. In a coordinate system - what is the origin?
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.
(0 -0)
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
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

23. When 2 lines are perpendicular to each other - their intersection forms 4 angles. What degree are these 4 angles?
A line is a 180-degree angle.
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.
90 degrees each.
Invert the second fraction (reciprocal) and multiply

24. HIGH: Rough est. of v2 =
S²
Groups - teams - or committees.
1.4
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)

25. In a coordinate system - identify the quadrants and describe their location.
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.
60%
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.
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.

26. An integer is divisible by 9 if...
The total # of possible outcomes.
(x+y)²
x² -2xy + y²
An integer is divisible by 9 if the sum of its digits is divisible by 9.

27. Convert to a percentage: 4/5
The formula is a² + b² + c² = d² where a - b - c are the dimensions of the figure and d is the diagonal.
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
180 degrees.
80%

28. How do you add or subtract fractions?
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
Percentage Change = Difference/Original * 100
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.
Find a common denominator and make equivalent fractions. Then add or subtract.

29. Explain how to solve for 7/¼
1/x^n For example - 6-² = 1/6² = 1/36
This equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28
A triangle in which one of the three interior angles is 90 degrees.
'Big' angles and 'Small' angles.

30. HIGH: What is the formula for the diagonal of any square?
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 ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
80%
S*v2

31. Define the range of a set of numbers.
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.
80%
1. Given event A: A + notA = 1.
6

32. What is the 'distributive law'?
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
x² -2xy + y²
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.
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.

33. HIGH: how do you calculate the surface area of a rectangular box?
25%
6
'Big' angles and 'Small' angles.
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.

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

35. HIGH: Describe how to deal with 2 sets of parentheses.
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)+
x²-y²
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
'Big' angles and 'Small' angles.

36. Define 'proportionate' values
Percentage Change = Difference/Original * 100
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
(0 -0)
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)+

37. What is a 'Right' triangle?
A line is a 180-degree angle.
40%
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
A triangle in which one of the three interior angles is 90 degrees.

38. Diameter of a circle?
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.
V=s³
A line is a 180-degree angle.
2r

39. How do you calculate the percentage of change?
Groups - teams - or committees.
Percentage Change = Difference/Original * 100
A circle'S perimeter is roughly 3x its diameter (the formula is pd).
Invert the second fraction (reciprocal) and multiply

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

41. Probability Formula
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.
Favorable Outcomes/Total Possible Outcomes
2r
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

42. How many angles are formed when 2 lines intersect? and what is the sum of these angles?
The value that appears most often in a data set.
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
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.

43. What are 'vertical angles'?
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
(x+y)²
Find a common denominator and make equivalent fractions. Then add or subtract.
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.

44. Explain how to divide fractions.
S²
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
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%.
Turn the second fraction upside down (find its reciprocal) and multiply. Example: 2/3 ÷ 4/5 = 2/3 * 5/4

45. How do you solve a combination?

46. An integer is divisible by 2 if...
An integer is divisible by 2 if its units digit is divisible by 2.
3:4:5 5:12:13
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
90 degrees each.

47. HIGH: What are the percentages for standard deviation?
2 - 14 - and 34. So - a Bell - standard deviation - or normal distribution curve would be segmented: | 2% | 14% | 34% |average score| 34% | 14% | 2% |
x²-y²
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.
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5

48. HIGH: What is the side ratio for a 30:60:90 triangle?
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
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.
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
2r

49. What number goes on the bottom of a probability fraction?
The total # of possible outcomes.
2r
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.
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.

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