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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. List all the prime numbers that are less than 30:
x² -2xy + y²
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
Multiply numerator times numerator and denominator times denominator.
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.

2. What is the sum of any 'big' angle and any 'Small' angle?
360 degrees
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'.
180 degrees.
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.

3. 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.
Not necessarily. This is a trick question - because x could be either positive or negative.
Multiply numerator times numerator and denominator times denominator.
An integer is divisible by 8 if its last three digits form a number that'S divisible by 8. For example - 11 -640.

4. What is the equation for a group problem?
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.
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.
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

5. Convert to a percentage: 4/5
80%
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.
V=s³
1/x^n For example - 6-² = 1/6² = 1/36

6. What'S the most important thing to remember about charts you'll see on the GRE?
360 degrees
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 - 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 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.

7. How do you multiply fractions?
Multiply numerator times numerator and denominator times denominator.
180 degrees
2pr -or- pd
The value that appears most often in a data set.

8. An integer is divisible by 2 if...
Bh
An integer is divisible by 2 if its units digit is divisible by 2.
40%
Not reading the problems carefully enough!

9. HIGH: How do you calculate the circumference of a circle?
2pr -or- pd
(x-y)²
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
x² -2xy + y²

10. What is one misleading characteristic of quadratic equations that will be exploited on the GRE?
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
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.
An integer is divisible by 8 if its last three digits form a number that'S divisible by 8. For example - 11 -640.
The formula is a² + b² + c² = d² where a - b - c are the dimensions of the figure and d is the diagonal.

11. An integer is divisible by 8 if...

12. How do you calculate the probability of EITHER one event OR another event happening? (Probability of A or B)
Groups - teams - or committees.
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5
Probability A + Probability B
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.

13. Probability Formula
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 8 if its last three digits form a number that'S divisible by 8. For example - 11 -640.
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
Favorable Outcomes/Total Possible Outcomes

14. Define the range of a set of numbers.
1.7
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.
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
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.

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

16. Area of a parallelogram?
The value that appears most often in a data set.
A 90-degree angle.
Bh
An integer is divisible by 5 if its units digit is either 0 or 5.

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

18. Explain how to solve for 7/¼
Example: 1 < x < 10
180 degrees
180 degrees.
This equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28

19. What causes 80% of errors on the math section of the GRE?
6
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.
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.
Not reading the problems carefully enough!

20. Explain how to use a 'Rate Pie'
1.7
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
1.4
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.

21. An integer is divisible by 5 if...
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.
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.
An integer is divisible by 5 if its units digit is either 0 or 5.
It will be a great advantage on test day to have your times table memorized from 1 through 15.

22. HIGH: What is the unfactored version of (x+y)² ?
x² + 2xy + y²
S*v2
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
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)+

23. How do you calculate the probability of two events in a row? (Probability of A and B)
Between 0 and 1.
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.
Probability A * Probability B
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2

24. HIGH: What is the factored version of (x+y)(x-y) ?
1. Given event A: A + notA = 1.
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%.
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'.
x²-y²

25. HIGH: What is a 'Right isosceles' triangle?
180 degrees.
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 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.
A=pr²

26. On the GRE - should you ever assume that diagrams are truthful?
Example: 1 < x < 10
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
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.
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.

27. What do permutation problems often ask for?
Arrangements - orders - schedules - or lists.
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
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.

28. Does order matter for a permutation? How about for a combination?
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.
Order does matter for a permutation - but does not matter for a combination.
1/x^n For example - 6-² = 1/6² = 1/36
'Big' angles and 'Small' angles.

29. How many degrees does a circle contain?
An integer is divisible by 9 if the sum of its digits is divisible by 9.
360 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
Turn the second fraction upside down (find its reciprocal) and multiply. Example: 2/3 ÷ 4/5 = 2/3 * 5/4

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

31. The three exterior angles of a triangle add up to...
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
90 degrees each.
V=pr²h (This is just the area multiplied by the height)
360 degrees

32. What number goes on the bottom of a probability fraction?
A=pr²
The total # of 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.
Probability A * Probability B

33. Convert to a percentage: 1/4
25%
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.
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.

34. HIGH: Area of a triangle?
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.
A radius
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
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

35. An integer is divisible by 9 if...
An integer is divisible by 9 if the sum of its digits is divisible by 9.
Turn the second fraction upside down (find its reciprocal) and multiply. Example: 2/3 ÷ 4/5 = 2/3 * 5/4
An integer is divisible by 2 if its units digit is divisible by 2.
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5

36. HIGH: How do you get rid of the fraction in this equation: 5x + 3/2 = 7x
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.
Multiply numerator times numerator and denominator times denominator.
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
2 - 14 - and 34. So - a Bell - standard deviation - or normal distribution curve would be segmented: | 2% | 14% | 34% |average score| 34% | 14% | 2% |

37. v4 =
2
Find the total - or whole - first - and then set up a Ratio Box.
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.

38. HIGH: What is the mode?
2
S*v2
Not reading the problems carefully enough!
The value that appears most often in a data set.

39. What is the formula to determine probability?
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
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
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
Percentage Change = Difference/Original * 100

40. How do you divide fractions?
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
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
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
Invert the second fraction (reciprocal) and multiply

41. HIGH: Simplify this: v75/v27
A triangle in which one of the three interior angles is 90 degrees.
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.
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.
'Big' angles and 'Small' angles.

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

43. HIGH: Rough est. of v3 =
'Big' angles and 'Small' angles.
V=pr²h (This is just the area multiplied by the height)
1.7
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

44. HIGH: What is the unfactored version of x²-y² ?
(x+y)(x-y)
An integer is divisible by 5 if its units digit is either 0 or 5.
80%
x² -2xy + y²

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 is a range expressed with inequalities?
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.
Example: 1 < x < 10
An integer is divisible by 8 if its last three digits form a number that'S divisible by 8. For example - 11 -640.

47. Solve this: v6 * -v6 = ?
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.
6
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.
(0 -0)

48. What do combination problems usually ask for?
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.
2 - 14 - and 34. So - a Bell - standard deviation - or normal distribution curve would be segmented: | 2% | 14% | 34% |average score| 34% | 14% | 2% |
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.
Groups - teams - or committees.

49. What is a 'Right' angle?
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.
A 90-degree angle.
Using a simple '3' is usually close enough. Just remember that p is slightly more than 3 - if a comparison is called for.
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

50. 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.
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
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'.