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. 50 < all primes< 60
53 - 59
A reflection about the axis.
No - only like radicals can be added.
54sqrt3. (divide the hexagon into 6 congruent equilateral triangles.

2. Hector invested $6000. Part was invested in account with 9% simple annual interest - and the rest in account with 7% simple annual interest. If he earned $490 in the first year of these investments - how much did he invest in each account?
Two equal sides and two equal angles.
288 (8 9 4)
$3 -500 in the 9% and $2 -500 in the 7%.
4725

3. 60 < all primes <70
Pi is the ratio of a circle'S circumference to its diameter.
61 - 67
23 - 29
A subset.

4. Is 0 even or odd?
A tangent is a line that only touches one point on the circumference of a circle.
(a - b)(a + b)
41 - 43 - 47
Even

5. Circumference of a circle?
16^8 - 64^5 = (4^3)^5 = 4^15 - 16^8=(4^2)^8 = 4^16
3sqrt4
13
Diameter(Pi)

6. What is the graph of f(x) shifted left c units or spaces?
$11 -448
F(x + c)
Its divisible by 2 and by 3.
53 - 59

7. If the two sides of a triangle are unequal then the longer side...
Area of the base X height = (pi)hr^2
Infinite.
Lies opposite the greater angle
Two angles whose sum is 90.

8. What is the 'Range' of a series of numbers?
90pi
The greatest value minus the smallest.
Factors are few - multiples are many.
The objects within a set.

9. What is the sum of the angles of a triangle?
The graph of 3(x - 1)^2 is a translation (shift) of the graph one unit or space to the right.
x = [(-b)+/- (sqrt b^2 - 4ac)]/2a
2^9 / 2 = 256
180 degrees

10. 70 < all primes< 80
The direction of the inequality is reversed.
71 - 73 - 79
83.333%
Yes - like radicals can be added/subtracted.

11. A number is divisible by 9 if...
The sum of digits is divisible by 9.
An expression with just one term (-6x - 2a^2)
1/(x^y)
The two xes after factoring.

12. What is the set of elements found in both A and B?
Relationship cannot be determined (what if x is negative?)
Part = Percent X Whole
The interesection of A and B.
12! / 5!7! = 792

13. What is the measure of an exterior angle of a regular pentagon?
Factors are few - multiples are many.
72
1
441000 = 1 10 10 10 21 * 21

14. 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)?
(a - b)(a + b)
90 degrees
41 - 43 - 47
y = (x + 5)/2

15. x^6 / x^3
The graph of 3(x - 1)^2 is a translation (shift) of the graph one unit or space to the right.
x^(6-3) = x^3
2
Two angles whose sum is 180.

16. Which quandrant is the lower right hand?
3/2 - 5/3
IV
Infinite.
The shortest arc between points A and B on a circle'S diameter.

17. Legs: 3 - 4. Hypotenuse?
An angle which is supplementary to an interior angle.
5
A set with no members - denoted by a circle with a diagonal through it.
441000 = 1 10 10 10 21 * 21

18. Surface area for a cylinder?
No - the input value has exactly one output.
A reflection about the origin.
62.5%
2(pi)r^2 + 2(pi)rh

19. In a regular polygon with n sides - the formula for the sum of interior angles
(n-2) x 180
6 : 1 : 2
The overlapping sections.
Part = Percent X Whole

20. What is the side length of an equilateral triangle with altitude 6?
3sqrt4
The overlapping sections.
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 second graph is less steep.

21. What are the roots of the quadrinomial x^2 + 2x + 1?
Its divisible by 2 and by 3.
(base*height) / 2
Move the decimal point to the right x places
The two xes after factoring.

22. Volume for a cylinder?
61 - 67
6
Area of the base X height = (pi)hr^2
Move the decimal point to the right x places

23. Can you add sqrt 3 and sqrt 5?
No - only like radicals can be added.
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.
An expression with just one term (-6x - 2a^2)
90pi

24. a^2 - b^2
37.5%
5
(a - b)(a + b)
G(x) = {x}

25. x^4 + x^7 =
x^(6-3) = x^3
1
Lies opposite the greater angle
x^(4+7) = x^11

26. To convert a decimal to a percent...
II
A term is a numerical constant or the product (or quotient) of a numerical constant and one or more variables. (3x - 4x^2 and 2a/c)
...multiply by 100.
Arc length = (n/360) x pi(2r) where n is the number of degrees.

27. Can you subtract 3sqrt4 from sqrt4?
16.6666%
16^8 - 64^5 = (4^3)^5 = 4^15 - 16^8=(4^2)^8 = 4^16
18
Yes - like radicals can be added/subtracted.

28. If 4500 is invested at a simple interest rate of 6% - what is the value of the investment after 10 months?
4725
A circle centered at -2 - -2 with radius 3.
4:5
IV

29. What is the 'Restricted domain of a function'?
An arc is a portion of a circumference of a circle.
4.25 - 6 - 22
1:1:sqrt2
When the function is not defined for all real numbers -; only a subset of the real numbers.

30. Simplify the expression (p^2 - q^2)/ -5(q - p)
4.25 - 6 - 22
(p + q)/5
37.5%
An infinite set.

31. If 10800 is invested at a simple interest rate of 4% - what is the value of the investment after 18 months?
180
$11 -448
27^(-4)
2(pi)r^2 + 2(pi)rh

32. Legs 6 - 8. Hypotenuse?
10
3sqrt4
6
The point of intersection of the systems.

33. What does the graph (x+2)^2 + (y+2)^2 = 9 look like?
A circle centered at -2 - -2 with radius 3.
The second graph is less steep.
(b + c)
All numbers multiples of 1.

34. Simplify 9^(1/2) X 4^3 X 2^(-6)?
3
Yes - like radicals can be added/subtracted.
.0004809 X 10^11
6

35. If Madagascar'S exports totaled 1.3 billion in 2009 - and 4% came from China - what was the value in millions of the country'S exports to China?
.0004809 X 10^11
Two angles whose sum is 180.
52
The greatest value minus the smallest.

36. Formula of rectangle where l increases by 20% and w decreases by 20%
$3 -500 in the 9% and $2 -500 in the 7%.
130pi
The overlapping sections.
x= (1.2)(.8)lw

37. A number is divisible by 3 if ...
(a - b)(a + b)
4725
An infinite set.
The sum of its digits is divisible by 3.

38. What is the 'Range' of a function?
(base*height) / 2
(b + c)
The set of output values for a function.
A grouping of the members within a set based on a shared characteristic.

39. 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?
2^9 / 2 = 256
All real numbers which can'T be expressed as a ratio of two integers - positive and negative (pi - -sqrt3)
9 : 25
The point of intersection of the systems.

40. Define a 'monomial'
13
61 - 67
An expression with just one term (-6x - 2a^2)
A chord is a line segment joining two points on a circle.

41. Which quadrant is the upper right hand?
I
10! / 3!(10-3)! = 120
31 - 37
288 (8 9 4)

42. What is an exterior angle?
A term is a numerical constant or the product (or quotient) of a numerical constant and one or more variables. (3x - 4x^2 and 2a/c)
The set of elements which can be found in either A or B.
III
An angle which is supplementary to an interior angle.

43. What is an arc of a circle?
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.
A reflection about the axis.
37.5%
An arc is a portion of a circumference of a circle.

44. What is the graph of f(x) shifted upward c units or spaces?
The set of elements found in both A and B.
7 / 1000
F(x) + c
13

45. What is the ratio of the surface area of a cube with an edge of 10 to the surface area of a rectangular solid with dimensions 2 - 4 - and 6?
All numbers which can be expressed as a ratio of two integers. (All integers and fractions.) (-2 - 1 - .25 - 1/2)
75:11
0
A central angle is an angle formed by 2 radii.

46. What is the name for a grouping of the members within a set based on a shared characteristic?
61 - 67
y = (x + 5)/2
A subset.
$11 -448

47. Formula to find a circle'S circumference from its diameter?
Two angles whose sum is 180.
C = (pi)d
2.592 kg
(p + q)/5

48. Length of an arc of a circle?
Even
Angle/360 x 2(pi)r
3
13

49. 3/8 in percent?
180
37.5%
20.5
The shortest arc between points A and B on a circle'S diameter.

50. What are 'Supplementary angles?'
4:9. The ratio of the areas of two similar triangles equals the square of the ratio of the corresponding sides.
Two angles whose sum is 180.
Undefined
53 - 59