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GRE Math 2

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. Does order matter for a permutation? How about for a combination?
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
Ac+ad+bc+bd
T1 * r^(n-1)/(r-1)
Order does matter for a permutation - but does not matter for a combination.

2. In a coordinate system - what is the origin?
(0 -0)
2(lw+wh+lh)
1. Given event A: A + notA = 1.
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.

3. a²+2ab+b²
(a+b)²
Sum of terms/number of terms
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 part of a circle that looks like a piece of pie. A sector is bounded by 2 radii and an arc of the circle.

4. a² - b² is equal to
(x+y)²
2 pi r
(a+b)(a-b)
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'.

5. Sector
(x-y)²
(a-b)²
The part of a circle that looks like a piece of pie. A sector is bounded by 2 radii and an arc of the circle.
Lw

6. What is the sum of the inside angles of an n-sided polygon?
(n-2)180
(a+b)²
Sum of terms/number of terms
1.4

7. In a parabola - if the first term is negative - the parabola ________.
y-y1=m(x-x1)
Opens down
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
A segment connecting the center of a circle to any point on the circle

8. length of a sector
2(pi)r(r+h)
x°/360 times (2 pi r) - where x is the degrees in the angle
(a-b)²
1.4

9. (a+b)(a-b)=
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
(y2-y1)/(x2-x1)
A²-b²
(n/2) * (t1+tn)

10. What kind of triangle is this: has two sides of equal length - and a 90 degree angle?
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.
(0 -0)
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.
2Length + 2width [or (length + width) x 2]

11. Perimeter of a square
T1 * r^(n-1)/(r-1)
4s (where s = length of a side)
A=?r2
(a+b)²

12. What is the prime factorization of 200?
?d OR 2?r
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.
2x2x2x5x5
y = k/x

13. Area of a triangle
½(base x height) [or (base x height)÷2]
1. Given event A: A + notA = 1.
2pir^2 + 2pir*h
Pir^2h

14. What is the probability?
The formula is a² + b² + c² = d² where a - b - c are the dimensions of the figure and d is the diagonal.
An ange whose vertex is the center of the circle
(a-b)²
Number of desired outcomes/number of total outcomes

15. If something is possible but not certain - what is the numeric range of probability of it happening?
Pi*d
4s
Between 0 and 1.
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.

16. In a parabola - if the first term is positive - the parabola ________.
The formula is a² + b² + c² = d² where a - b - c are the dimensions of the figure and d is the diagonal.
S² - where s = length of a side
Opens up
(pi)r^2(h)

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

18. Area of a sector
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x 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.
x°/360 times (?r²) - where x is the degrees in the angle
Number of desired outcomes/number of total outcomes

19. How do you get rid of the fraction in this equation: 5x + 3/2 = 7x
T1 * r^(n-1)/(r-1)
Opens down
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.
(a+b)(a-b)

20. Circumference of a circle using radius
Opens up
2pi*r
Pir^2h
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2

21. Perimeter of polygon
x² + 2xy + y²
Sum of the lengths of the sides
4/3pir^3
The part of a circle that looks like a piece of pie. A sector is bounded by 2 radii and an arc of the circle.

22. Area of Circle
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
4/3pir^3
4pir^2
Pi*r^2

23. Perimeter of a rectangle
2Length + 2width [or (length + width) x 2]
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.
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.
A segment connecting the center of a circle to any point on the circle

24. How do you multiply and divide square roots?
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
(pi)r^2(h)
?d OR 2?r
An ange whose vertex is the center of the circle

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

26. What do combination problems usually ask for?
(n degrees/360) * (pi)r^2
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5
Groups - teams - or committees.
A+b

27. Chord
Equal
Opens up
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
The distance from one point on the circle to another point on the circle.

28. Define 'proportionate' values
Proportionate values are equivalent. Example: 1/2 and 4/8 are proportionate - but 1/2 and 2/3 are not.
Number of desired outcomes/number of total outcomes
1
x² + 2xy + y²

29. What is the area of a triangle?
1/2bh
Less
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
2Length + 2width [or (length + width) x 2]

30. Volume of pyramid
1/3Bh
The four big angles are equal and the four small angles are equal
Ac+ad+bc+bd
2pi*r

31. In a coordinate system - identify the quadrants and describe their location.
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.
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.
(a-b)²
1

32. How do you find the sum of an arithmetic sequence?
Middle term
The four big angles are equal and the four small angles are equal
2pi*r
(n/2) * (t1+tn)

33. Slope
(y2-y1)/(x2-x1)
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 circle'S perimeter is roughly 3x its diameter (the formula is pd).
(x-y)²

34. What is the point-slope form?
S² - where s = length of a side
2Length + 2width [or (length + width) x 2]
(y-y1)=m(x-x1)
Groups - teams - or committees.

35. What is the average?
Total distance/total time
?d OR 2?r
Sum of terms/number of terms
(n degrees/360) * (pi)r^2

36. What is a '30:60:90' triangle?
Opens up
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.
Percentage Change = Difference/Original * 100
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

37. What is the equation of a line?

38. What is the side ratio for a Right Isosceles triangle?
Order does matter for a permutation - but does not matter for a combination.
x°/360 times (?r²) - where x is the degrees in the angle
2(lw+wh+lh)
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.

39. If x² = 144 - does v144 = x?
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
The distance from one point on the circle to another point on the circle.
b±[vb²-4ac]/2a
Not necessarily. This is a trick question - because x could be either positive or negative.

40. What is the 'Third side' rule for triangles?
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5
(0 -0)
N x M
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.

41. Circumference of a circle
?d OR 2?r
A=?r2
Sum of the lengths of the sides
C =?d

42. The length of one side of any triangle is ____ than the sum of the other two sides.
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.
1/2 h (b1 + b2)
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
Less

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

44. Area of a circle
?d OR 2?r
Total distance/total time
Lwh
?r²

45. What'S the most important thing to remember about charts you'll see on the GRE?
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. 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.
?d OR 2?r
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.

46. 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.
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.
Negative
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.

47. How do you calculate a diagonal inside a 3-dimensional rectangular box?
The formula is a² + b² + c² = d² where a - b - c are the dimensions of the figure and d is the diagonal.
4s
Bh
(a-b)(a+b)

48. What is the average speed?
Sum of the lengths of the sides
1.4
Total distance/total time
1.7

49. Area of a trapezoid
½(b1 +b2) x h [or (b1 +b2) x h÷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.
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.
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

50. What is the factored version of x² -2xy + y² ?
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.
(x-y)²
The total # of possible outcomes.
Bh