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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: Describe how to deal with 2 sets of parentheses.
1
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)+
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.
The total # of possible outcomes.

2. How precise do you need to be - using p on the GRE?

3. HIGH: To divide powers with the same base...
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.
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.
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.
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5

4. What is an 'equilateral' triangle?
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
Arrangements - orders - schedules - or lists.
The total # of possible outcomes.

5. HIGH: What is the side ratio for a 30:60:90 triangle?
The average - mean - median - or mode.
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.
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.

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

7. HIGH: Rough est. of v1 =
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
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.
1
Favorable Outcomes/Total Possible Outcomes

8. List two odd behaviors of exponents
60%
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.
A 90-degree angle.
Probability A * Probability B

9. An integer is divisible by 5 if...
The # falling in the center of an ordered data set
An integer is divisible by 5 if its units digit is either 0 or 5.
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
4 angles are formed. Their sum is 360 degrees

10. What'S the most important thing to remember about charts you'll see on the GRE?
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.
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.
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.

11. Convert to a percentage: 3/5
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)+
Arrangements - orders - schedules - or lists.
60%
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2

12. 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
x²-y²
1/x^n For example - 6-² = 1/6² = 1/36
An integer is divisible by 2 if its units digit is divisible by 2.

13. What do permutation problems often ask for?
Arrangements - orders - schedules - or lists.
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.
A circle'S perimeter is roughly 3x its diameter (the formula is pd).
(x-y)²

14. HIGH: What is the Pythagorean theorem?

15. v4 =
3:4:5 5:12:13
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
1/x^n For example - 6-² = 1/6² = 1/36
2

16. HIGH: What is the factored version of (x+y)(x-y) ?
360 degrees
x²-y²
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.
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'.

17. For a bell curve - what three terms might be used to describe the number in the middle?
The average - mean - median - or mode.
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.
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
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.

18. How do you solve a combination?

19. Convert to a percentage: 2/5
4 angles are formed. Their sum is 360 degrees
This equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28
40%
Find a common denominator and make equivalent fractions. Then add or subtract.

20. What kind of triangle is this: has two sides of equal length - and a 90 degree angle?
25%
'Big' angles and 'Small' 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.
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.

21. Define a factorial of a number - and how it is written.
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.
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
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.

22. HIGH: What are the percentages for standard deviation?
40%
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 5 if its units digit is either 0 or 5.
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

23. Area of a parallelogram?
1/x^n For example - 6-² = 1/6² = 1/36
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
Bh
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.

24. What is a 'Right' angle?
Not necessarily. This is a trick question - because x could be either positive or negative.
A 90-degree angle.
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.
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

25. How do you calculate the percentage of change?
The average - mean - median - or mode.
Percentage Change = Difference/Original * 100
Invert the second fraction (reciprocal) and multiply
1.7

26. If something is possible but not certain - what is the numeric range of probability of it happening?
1.4
360 degrees
1.7
Between 0 and 1.

27. 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
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.
V=pr²h (This is just the area multiplied by the height)

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

29. What is the 'Third side' rule for triangles?
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.
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
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.

30. How many degrees does a circle contain?
1
360 degrees
6
4 angles are formed. Their sum is 360 degrees

31. HIGH: List the two most common side ratios for right triangles
3:4:5 5:12:13
2r
2pr -or- pd
60%

32. How do you solve a permutation?
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
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
This equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28
3:4:5 5:12:13

33. When 2 lines are perpendicular to each other - their intersection forms 4 angles. What degree are these 4 angles?
A radius
90 degrees each.
The # falling in the center of an ordered data set
1.4

34. a² - b² is equal to
Percentage Change = Difference/Original * 100
Not necessarily. This is a trick question - because x could be either positive or negative.
(a+b)(a-b)
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.

35. What is the equation for a group problem?
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
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.
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
1/x^n For example - 6-² = 1/6² = 1/36

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

37. HIGH: x^-n is equal to
Find a common denominator and make equivalent fractions. Then add or subtract.
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
S*v2
1/x^n For example - 6-² = 1/6² = 1/36

38. What number goes on the bottom of a probability fraction?
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 total # of possible outcomes.
V=s³
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'.

39. HIGH: How do you calculate the circumference of a circle?
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
For RIGHT triangles only: c² = a² + b² 'c' is the length of the hypotenuse; 'a' and 'b' are the other two sides ('legs')
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
2pr -or- pd

40. HIGH: What is a '30:60:90' triangle?
2
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
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.
Not necessarily. This is a trick question - because x could be either positive or negative.

41. HIGH: Rough est. of v3 =
A 90-degree angle.
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.
Groups - teams - or committees.
1.7

42. HIGH: Define the formula for calculating slope.
1. Given event A: A + notA = 1.
Slope = rise/run. Find the change in y-coordinates (rise) and the change in x-coordinates (run) to calculate.
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.
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.

43. What degree angle is a line?
Not reading the problems carefully enough!
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
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.

44. HIGH: What is the unfactored version of (x-y)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.
A radius
x² -2xy + y²
Find a common denominator and make equivalent fractions. Then add or subtract.

45. On the GRE - should you ever assume that diagrams are truthful?
It will be a great advantage on test day to have your times table memorized from 1 through 15.
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
An integer is divisible by 5 if its units digit is either 0 or 5.

46. HIGH: What is the factored version of x² + 2xy + y² ?
(x+y)²
x² -2xy + y²
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.
1.7

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

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

49. Simplify this: v32
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.
V=pr²h (This is just the area multiplied by the height)
A circle'S perimeter is roughly 3x its diameter (the formula is pd).
Find a common denominator and make equivalent fractions. Then add or subtract.

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