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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. Convert to a percentage: 4/5
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
Not necessarily. This is a trick question - because x could be either positive or negative.
80%
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.

2. How do you add or subtract fractions?
60%
An integer is divisible by 2 if its units digit is divisible by 2.
Find a common denominator and make equivalent fractions. Then add or subtract.
3:4:5 5:12:13

3. What is the key to dealing with ratio questions?
Find the total - or whole - first - and then set up a Ratio Box.
x² + 2xy + y²
'Big' angles and 'Small' angles.
360 degrees

4. What number goes on the bottom of a probability fraction?
The average - mean - median - or mode.
Between 0 and 1.
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.
The total # of possible outcomes.

5. What is the sum of any 'big' angle and any 'Small' angle?
The total # of possible outcomes.
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.
180 degrees.
Probability A * Probability B

6. v4 =
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
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.
Not reading the problems carefully enough!

7. How do you calculate the percentage of change?
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.
S²
Percentage Change = Difference/Original * 100
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.

8. What do combination problems usually ask for?
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%.
Multiply numerator times numerator and denominator times denominator.
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
Groups - teams - or committees.

9. What is the formula to determine probability?
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
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 equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28
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.

10. Probability Formula
Probability A * Probability B
Percentage Change = Difference/Original * 100
2r
Favorable Outcomes/Total Possible Outcomes

11. What is the factored version of x² -2xy + y² ?
x² -2xy + y²
(x-y)²
25%
Add the exponents - retain the base. for example - x² + x5 = x²+5 = x7

12. HIGH: What are the percentages for standard deviation?
x² + 2xy + y²
Multiply numerator times numerator and denominator times denominator.
Groups - teams - or committees.
2 - 14 - and 34. So - a Bell - standard deviation - or normal distribution curve would be segmented: | 2% | 14% | 34% |average score| 34% | 14% | 2% |

13. What is the 'Third side' rule for triangles?
A 90-degree angle.
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
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.
180 degrees

14. HIGH: To divide powers with the same base...
3:4:5 5:12:13
Invert the second fraction (reciprocal) and multiply
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5
The # falling in the center of an ordered data set

15. An integer is divisible by 2 if...
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.
Find a common denominator and make equivalent fractions. Then add or subtract.
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.

16. HIGH: how do you calculate a diagonal inside a 3-dimensional rectangular box?
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.
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3
1/x^n For example - 6-² = 1/6² = 1/36
The formula is a² + b² + c² = d² where a - b - c are the dimensions of the figure and d is the diagonal.

17. If something is possible but not certain - what is the numeric range of probability of it happening?
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.
Between 0 and 1.
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
360 degrees

18. HIGH: what is the side ratio for a Right Isosceles triangle?
A circle'S perimeter is roughly 3x its diameter (the formula is pd).
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
The formula is a² + b² + c² = d² where a - b - c are the dimensions of the figure and d is the diagonal.
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. What kind of triangle is this: has two sides of equal length - and a 90 degree angle?
x² + 2xy + y²
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.
The formula is a² + b² + c² = d² where a - b - c are the dimensions of the figure and d is the diagonal.
x² -2xy + y²

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

21. What'S the most important thing to remember about charts you'll see on the GRE?
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.
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.
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

22. HIGH: Simplify this: v75/v27
(0 -0)
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.
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.
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.

23. Explain the special properties of zero.
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.
(0 -0)
A=pr²
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)+

24. What are the side ratios for a 30:60:90 triangle?
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.
The value that appears most often in a data set.
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.
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.

25. a² - b² is equal to
This equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28
4 angles are formed. Their sum is 360 degrees
(a+b)(a-b)
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

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

27. HIGH: What is the mode?
The value that appears most often in a data set.
(x-y)²
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.
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)

28. How do you solve a combination?

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

30. On the GRE - should you ever assume that diagrams are truthful?
The # falling in the center of an ordered data set
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
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

31. HIGH: Area of a circle
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%.
Multiply numerator times numerator and denominator times denominator.
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.
A=pr²

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

33. HIGH: What is a '30:60:90' triangle?
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.
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
(a+b)(a-b)

34. When a pair of parallel lines is intersected by another line - two types of angles are formed. What are they?

35. HIGH: What is the unfactored version of (x+y)² ?
40%
x² + 2xy + y²
V=pr²h (This is just the area multiplied by the height)
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.

36. How is a range expressed with inequalities?
Interior angles are equal: 60:60:60 degrees each. All sides are equal length.
60%
Example: 1 < x < 10
A triangle in which one of the three interior angles is 90 degrees.

37. How do you divide fractions?
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.
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.
Add the exponents - retain the base. for example - x² + x5 = x²+5 = x7
Invert the second fraction (reciprocal) and multiply

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

39. HIGH: List the two most common side ratios for right triangles
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.
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.
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
3:4:5 5:12:13

40. What is a 'Right' angle?
60%
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.
A 90-degree angle.

41. HIGH: What is the median?
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.
An integer is divisible by 2 if its units digit is divisible by 2.
Invert the second fraction (reciprocal) and multiply
The # falling in the center of an ordered data set

42. List two odd behaviors of exponents
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.
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.
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

43. Explain how to use a 'Rate Pie'
(x+y)²
An integer is divisible by 6 if it'S divisible by BOTH 2 and 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
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

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

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

46. The three exterior angles of a triangle add up to...
x²-y²
360 degrees
Example: 1 < x < 10
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.

47. The three interior angles of a triangle add up to...
360 degrees
180 degrees
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 5 if its units digit is either 0 or 5.

48. An integer is divisible by 9 if...
An integer is divisible by 9 if the sum of its digits is divisible by 9.
80%
360 degrees
(0 -0)

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

50. What is the equation for a group problem?
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
ZONE-F numbers: Zero - One - Negatives - Extreme values - Fractions
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.
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