Test your basic knowledge |

GRE Math: Common Errors

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. (-1)^3 =
All the numbers on the number line (negative - rational - irrational - decimal - integer). All the numbers on the GRE are real. (-2 - 1 - .25 - 1/2 - pi)
A subset.
4:9. The ratio of the areas of two similar triangles equals the square of the ratio of the corresponding sides.
1

2. How to determine percent increase?
(amount of increase/original price) x 100%
5
A reflection about the origin.
(amount of decrease/original price) x 100%

3. Solve the quadratic equation ax^2 + bx + c= 0
N! / (k!)(n-k)!
7 / 1000
1/a^6
x = [(-b)+/- (sqrt b^2 - 4ac)]/2a

4. x^6 / x^3
9 & 6/7
The angle intersecting the circumference is always the largest angle - and is always 90 degrees.
x^(6-3) = x^3
52

5. What is the absolute value function?
G(x) = {x}
16.6666%
Ax^2 + bx + c where a -b and c are constants and a /=0
(a + b)^2

6. Suppose that the graph of f(x) is the result of stretching y=x + 5 away from the x-axis by a factor of 2. What is the new equation for the graph f(x)?
y = (x + 5)/2
10! / (10-3)! = 720
Sector area = (n/360) X (pi)r^2
The union of A and B.

7. A triangle is inscribed in a semi circle with legs 5 and 12. What is the circumfermence of the semicircle?
Arc length = (n/360) x pi(2r) where n is the number of degrees.
11 - 13 - 17 - 19
13pi / 2
.0004809 X 10^11

8. What is the 'Range' of a series of numbers?
The greatest value minus the smallest.
The interesection of A and B.
1
It is a function defined by more than one equation - where each equation applies to a different part of the domain of the function.

9. What is the 'Solution' for a system of linear equations?
The curve opens downward and the vertex is the maximum point on the graph.
The point of intersection of the systems.
F(x) - c
x= (1.2)(.8)lw

10. 10<all primes<20
11 - 13 - 17 - 19
No - the input value has exactly one output.
... the square of the ratios of the corresponding sides.
The objects within a set.

11. What is the formula for computing simple interest?
1 & 37/132
A = I (1 + rt)
10
72

12. Which is greater? 27^(-4) or 9^(-8)
27^(-4)
A set with a number of elements which can be counted.
28. n = 8 - k = 2. n! / k!(n-k)!
2

13. Ratio of ages of Anna and Emma is 3:5 and of Emma and Nicolas is 3:5. What is the ratio of Anna to Nicholas' ages?
An algebraic expression is a combination of one of more terms. Terms in an expression are separated by either addition or subtraction signs. (3xy - 4ab - -5cd - x^2 + x - 1)
9 : 25
1 & 37/132
Two angles whose sum is 90.

14. 1/8 in percent?
3 - -3
Yes - like radicals can be added/subtracted.
12.5%
5

15. Legs 6 - 8. Hypotenuse?
C = 2(pi)r
A subset.
10
10! / 3!(10-3)! = 120

16. What are the irrational numbers?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

17. A cylinder has a surface area of 22pi. If the cylinder has a height of 10 - what is the radius?
12sqrt2
1
20.5
x= (1.2)(.8)lw

18. Simplify (a^2 + b)^2 - (a^2 - b)^2
A= I (1 + (r/c))^tC - where I is the investment - C is the number of times compounded annually - and t is the number of years.
Yes - because you can factor out a perfect square (36). Sqrt(36 x 2) = sqrt36 X sqrt2 = 6sqrt2.
5 OR -5
4a^2(b)

19. x^2 = 9. What is the value of x?
C = (pi)d
6
3 - -3
(a - b)^2

20. Formula for the area of a circle?
An expression with just one term (-6x - 2a^2)
72
A = pi(r^2)
23 - 29

21. What are complementary angles?
Two angles whose sum is 90.
11 - 13 - 17 - 19
1:sqrt3:2
$3 -500 in the 9% and $2 -500 in the 7%.

22. The objects in a set are called two names:
Members or elements
90
16.6666%
I

23. 5 bakeries sell an average of 300 muffins per bakery per day. If 2 stop making muffins but the total muffins sold stays the same - what is the average of muffins per bakery sold among the remaining?
1:1:sqrt2
Yes - like radicals can be added/subtracted.
500
All numbers which can be expressed as a ratio of two integers. (All integers and fractions.) (-2 - 1 - .25 - 1/2)

24. Volume for a cylinder?
8
5
54sqrt3. (divide the hexagon into 6 congruent equilateral triangles.
Area of the base X height = (pi)hr^2

25. (12sqrt15) / (2sqrt5) =
Indeterminable.
x= (1.2)(.8)lw
1
(12/2) x (sqrt15 / sqrt5) = 6sqrt3

26. What does the graph x^2 + y^2 = 64 look like?
All numbers multiples of 1.
A circle centered on the origin with radius 8.
441000 = 1 10 10 10 21 * 21
The point of intersection of the systems.

27. What is the set of elements which can be found in either A or B?
The union of A and B.
Angle/360 x (pi)r^2
Move the decimal point to the right x places
A circle centered on the origin with radius 8.

28. Convert 0.7% to a fraction.
7 / 1000
288 (8 9 4)
... the square of the ratios of the corresponding sides.
x = [(-b)+/- (sqrt b^2 - 4ac)]/2a

29. In a regular polygon with n sides - the formula for the sum of interior angles
2^9 / 2 = 256
48
(p + q)/5
(n-2) x 180

30. What are the smallest three prime numbers greater than 65?
Relationship cannot be determined (what if x is negative?)
12! / 5!7! = 792
67 - 71 - 73
83.333%

31. 1/6 in percent?
16.6666%
Even
1:1:sqrt2
x^(6-3) = x^3

32. (a^-1)/a^5
G(x) = {x}
1
The set of input values for a function.
1/a^6

33. 40 < all primes<50
(a + b)^2
441000 = 1 10 10 10 21 * 21
2
41 - 43 - 47

34. Define an 'expression'.
11 - 13 - 17 - 19
An algebraic expression is a combination of one of more terms. Terms in an expression are separated by either addition or subtraction signs. (3xy - 4ab - -5cd - x^2 + x - 1)
4sqrt3. The triangle can be divided into two equal 30-60-90 triangles with side 6 as the side in which 6 = xsqrt3. So x =2sqrt3...
The overlapping sections.

35. Describe the relationship between 3x^2 and 3(x - 1)^2
Infinite.
0
The graph of 3(x - 1)^2 is a translation (shift) of the graph one unit or space to the right.
3/2 - 5/3

36. What are the real numbers?
(a - b)(a + b)
62.5%
F(x) - c
All the numbers on the number line (negative - rational - irrational - decimal - integer). All the numbers on the GRE are real. (-2 - 1 - .25 - 1/2 - pi)

37. What is the 'domain' of a function?
The set of input values for a function.
Yes - like radicals can be added/subtracted.
Divide by 100.
7 / 1000

38. What is the formula for compounded interest?
A= I (1 + (r/c))^tC - where I is the investment - C is the number of times compounded annually - and t is the number of years.
288 (8 9 4)
Even
2

39. What is the graph of f(x) shifted downward c units or spaces?
Undefined
1
53 - 59
F(x) - c

40. Suppose that the graph of f(x) is the result of sliding the graph of y=2x^2 down 3 units of spaces. What is the new equation?
72
1
75:11
y = 2x^2 - 3

41. Suppose you have a set of n objects - and you want to select k of them - but the order doesn'T matter. What formula do you use to determine the number of combinations of n objects taken k at a time?
Pi is the ratio of a circle'S circumference to its diameter.
N! / (k!)(n-k)!
48
Relationship cannot be determined (what if x is negative?)

42. Simplify 4sqrt21 X 5sqrt2 / 10sqrt7
(12/2) x (sqrt15 / sqrt5) = 6sqrt3
Use Pythagorean theorem twice. (Once across the surface and then a is the diagonal of surface and b is an edge).
Angle/360 x 2(pi)r
2sqrt6

43. Employee X is paid 19.50 per hour no matter how many a week. Employee Y earns 18 for the first 40 and 1.5 the hourly wage for every hour after that. If both earned the same amount and worked the same in one week - how many did each work?
288 (8 9 4)
A grouping of the members within a set based on a shared characteristic.
48
20.5

44. Evaluate (4^3)^2
4096
A = pi(r^2)
Expressing a number as the product of a decimal between 1 and 10 - and a power of 10.
4.25 - 6 - 22

45. What are the members or elements of a set?
(n-2) x 180
87.5%
The objects within a set.
Even

46. Can you add sqrt 3 and sqrt 5?
No - only like radicals can be added.
(a + b)^2
4sqrt3. The triangle can be divided into two equal 30-60-90 triangles with side 6 as the side in which 6 = xsqrt3. So x =2sqrt3...
6 : 1 : 2

47. What are the integers?
II
All numbers multiples of 1.
x^(4+7) = x^11
The point of intersection of the systems.

48. 1:1:sqrt2 is the ratio of the sides of what kind of triangle?
16^8 - 64^5 = (4^3)^5 = 4^15 - 16^8=(4^2)^8 = 4^16
An isosceles right triangle.
1
83.333%

49. a^2 - b^2 =
The empty set - denoted by a circle with a diagonal through it.
71 - 73 - 79
$11 -448
(a - b)(a + b)

50. What is the ratio of the sides of a 30-60-90 triangle?
75:11
1:sqrt3:2
62.5%
0