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

2. What causes 80% of errors on the math section of the GRE?
A line is a 180-degree angle.
2r
An integer is divisible by 2 if its units digit is divisible by 2.
Not reading the problems carefully enough!

3. HIGH: What is the formula for the diagonal of any square?
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.
(# of possible outcomes that satisfy the condition) ÷ (total # of possible outcomes)
S*v2
360 degrees

4. What are the side ratios for a 30:60:90 triangle?
80%
4 angles are formed. Their sum is 360 degrees
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
Ratio of sides is x : xv3 : 2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.

5. HIGH: x^-n is equal to
This equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28
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.
1/x^n For example - 6-² = 1/6² = 1/36
The ratio of sides is x:x:xv2 - where xv2 is the hypotenuse.

6. How do you add or subtract fractions?
A 90-degree angle.
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.
Find a common denominator and make equivalent fractions. Then add or subtract.
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.

7. An integer is divisible by 3 if...
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.
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.
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
(x+y)(x-y)

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

9. HIGH: What is the factored version of (x+y)(x-y) ?
Turn the second fraction upside down (find its reciprocal) and multiply. Example: 2/3 ÷ 4/5 = 2/3 * 5/4
x²-y²
Example: 1 < x < 10
Quadrant 1 is top right. Q 2 is top left. Q 3 is bottom left. Q 4 is bottom right.

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

11. The probability of an event happening and the probability of an event NOT happening must add up to what number?
(0 -0)
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.
1. Given event A: A + notA = 1.
Invert the second fraction (reciprocal) and multiply

12. How do you solve a combination?

13. HIGH: What are the percentages for standard deviation?
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
360 degrees
2 - 14 - and 34. So - a Bell - standard deviation - or normal distribution curve would be segmented: | 2% | 14% | 34% |average score| 34% | 14% | 2% |
This equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28

14. What is a 'Right' triangle?
x² + 2xy + y²
A circle'S perimeter is roughly 3x its diameter (the formula is pd).
V=pr²h (This is just the area multiplied by the height)
A triangle in which one of the three interior angles is 90 degrees.

15. In a coordinate system - what is the origin?
Not reading the problems carefully enough!
Slope = rise/run. Find the change in y-coordinates (rise) and the change in x-coordinates (run) to calculate.
(0 -0)
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.

16. HIGH: Volume of a cube?
Invert the second fraction (reciprocal) and multiply
(x-y)²
V=s³
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

17. What is the name of a line that extends from the center of a circle to the edge of a circle?
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
Example: 1 < x < 10
A radius

18. On the GRE - should you ever assume that diagrams are truthful?
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
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.
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.
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.

19. HIGH: How do you multiply and divide square roots?
Favorable Outcomes/Total Possible Outcomes
It will be a great advantage on test day to have your times table memorized from 1 through 15.
Like any other number. For example - v3*v12 = v36 = 6 For example - v(16/4) = v16/v4 = 4/2 = 2
2

20. How do you solve a permutation?
For RIGHT triangles only: c² = a² + b² 'c' is the length of the hypotenuse; 'a' and 'b' are the other two sides ('legs')
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.
Percentage Change = Difference/Original * 100
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

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

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

23. An integer is divisible by 9 if...
Add the exponents - retain the base. for example - x² + x5 = x²+5 = x7
360 degrees
An integer is divisible by 9 if the sum of its digits is divisible by 9.
x² -2xy + y²

24. HIGH: Define the formula for calculating slope.
Slope = rise/run. Find the change in y-coordinates (rise) and the change in x-coordinates (run) to calculate.
The value that appears most often in a data set.
1/1
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.

25. HIGH: To divide powers with the same base...
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 circle'S perimeter is roughly 3x its diameter (the formula is pd).
Favorable Outcomes/Total Possible Outcomes
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5

26. HIGH: How do you get rid of the fraction in this equation: 5x + 3/2 = 7x
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.
1. Given event A: A + notA = 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.
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.

27. An integer is divisible by 5 if...
A triangle in which one of the three interior angles is 90 degrees.
An integer is divisible by 5 if its units digit is either 0 or 5.
A=pr²
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.

28. An integer is divisible by 2 if...
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
S*v2
An integer is divisible by 2 if its units digit is divisible by 2.
2r

29. What are 'vertical angles'?
For RIGHT triangles only: c² = a² + b² 'c' is the length of the hypotenuse; 'a' and 'b' are the other two sides ('legs')
2
Vertical angles are the angles that are across from each other when 2 lines intersect. Vertical angles are always equal.
Example: 1 < x < 10

30. What number goes on the bottom of a probability fraction?
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.
(x+y)²
(a+b)(a-b)
The total # of possible outcomes.

31. Simplify this: v32
1.4
V32 = v16*2. We can take the square root of 16 and move it outside the square root symbol - = 4v2.
(x+y)(x-y)
3:4:5 5:12:13

32. How do you calculate the probability of two events in a row? (Probability of A and B)
Not necessarily. This is a trick question - because x could be either positive or negative.
Probability A * Probability B
This equals 7 ÷¼ - or 7/1 ÷ 1/4 = 7/1 * 4/1 = 28/1 = 28
60%

33. What'S the most important thing to remember about charts you'll see on the GRE?
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.
A triangle in which one of the three interior angles is 90 degrees.
A=pr²
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.

34. If x² = 144 - does v144 = x?
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.
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
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.
Not necessarily. This is a trick question - because x could be either positive or negative.

35. Area of a square?
S²
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.
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.
V=s³

36. How many degrees does a circle contain?
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3
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.
360 degrees
The total # of possible outcomes.

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

38. v4 =
2
The average - mean - median - or mode.
1/x^n For example - 6-² = 1/6² = 1/36
S*v2

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

40. Explain how to use an 'Average Pie'
An integer is divisible by 8 if its last three digits form a number that'S divisible by 8. For example - 11 -640.
An integer is divisible by 2 if its units digit is divisible by 2.
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.
Draw a circle. The top half holds the Total. The bottom left quadrant holds Number of Things. Bottom right holds Average.

41. HIGH: What is the unfactored version of x²-y² ?
Multiply numerator times numerator and denominator times denominator.
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
(x+y)(x-y)
1.7

42. HIGH: What is the factored version of x² + 2xy + y² ?
An integer is divisible by 5 if its units digit is either 0 or 5.
(x+y)²
Total of the elements divided by the number of elements. Example: (4 -6 -7) -- add 4+6+7 = 17 and divide by 3
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

43. If something is possible but not certain - what is the numeric range of probability of it happening?
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.
Between 0 and 1.
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.
Invert the second fraction (reciprocal) and multiply

44. Explain how to divide fractions.
x² + 2xy + y²
Find the total - or whole - first - and then set up a Ratio Box.
80%
Turn the second fraction upside down (find its reciprocal) and multiply. Example: 2/3 ÷ 4/5 = 2/3 * 5/4

45. HIGH: How do you multiply powers with the same base?
Add the exponents - retain the base. for example - x² + x5 = x²+5 = x7
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.
Subtract the exponents - retain the base For example - x? ÷ x4 = x?-4 = x5

46. Convert to a percentage: 2/5
1.4
40%
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
The value that appears most often in a data set.

47. HIGH: Volume of a cylinder?
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.
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.
V=pr²h (This is just the area multiplied by the height)
An integer is divisible by 6 if it'S divisible by BOTH 2 and 3.

48. Explain how to use a 'Rate Pie'
A=1/2bh. The height of the triangle must be measured by a line perpendicular to the base.
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
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.
Multiply numerator times numerator and denominator times denominator.

49. List all the prime numbers that are less than 30:
2 -3 -5 -7 -11 -13 -17 -19 -23 -29. Note that 0 and 1 are not prime numbers.
An integer is divisible by 5 if its units digit is either 0 or 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
An integer is divisible by 2 if its units digit is divisible by 2.

50. HIGH: What is the side ratio for a 30:60:90 triangle?
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.
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.
No. Never believe what you see - only what you read. GRE diagrams are often deliberately designed to be misleading or confusing.
Ratio of sides is x:xv3:2x - where x is the base - xv3 is the height - and 2x is the hypotenuse.