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GMAT Quick Math And Formulas

Subjects : gmat, 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. Express 9^1/2 as a radical
2
83.33%
8
= the square root of 9 = 3

2. 6^4
196
1296
16
256

3. to multiple powers (or raise a power to a power)
Multiply the exponents 7^2(^3) = 7^6
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120
128
16

4. a^3-b^3
(a-b)(a^2+ab+b^2)
16.67%
16.66%
289

5. √ 6
2.449
196
16.67%
A^2 - 2ab + b^2

6. Prime Numbers between 1 - 100 (total of 25)
8
{2 -3 -5 -7 -11 -13 -17 -19 -23 -29 -31 -37 -41 -43 -47 -53 -59 -61 -67 -71 -73 -79 -83 -89 -97}
1296
16.67%

7. √ 2
√25.16 = √25 . √16 = 5.4 - √50 . √18 = √50.18 = √900 = 30 - √144:16 = √144 : √16 = 12/4 = 3
= the cube root of 8 = 2
= the square root of 9 = 3
1.41

8. a^3+b^3
361
1.41
(a+b)(a^2-ab+b^2)
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120

9. 1/4
256
(A+B)(A-B)
25%
324

10. 12^2
256
2.23
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4
144

11. to multiple powers with the same base...
64
Add the exponents and keep the base 7^3 x 7^5 = 7^8
32
...yields a positive result (-1)^2 = 1

12. a negative number raised to an even power...
= the square root of 9 = 3
...yields a positive result (-1)^2 = 1
121
361

13. 2^9
256
512
7776
(a+b)(a^2-ab+b^2)

14. 3/4
1024
8
75%
121

15. Multiples of 15
2
= the cube root of 8 = 2
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120
= the square root of 9 = 3

16. √ 3
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120
2.449
1.73
83.33%

17. 15^2
Add the exponents and keep the base 7^3 x 7^5 = 7^8
225
1024
A^2 - 2ab + b^2

18. √ 625
16.66%
64
25
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3

19. 1/5
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120
A^2 - 2ab + b^2
20%
121

20. 5^4
64
Add the exponents and keep the base 7^3 x 7^5 = 7^8
7776
625

21. raising a fraction between zero and 1 to a power...
50%
...yields a smaller result (1/2)^2 = 1/4
512
256

22. √25+16 = √41
8.33%
You cannot simplify this one
...yields a negative result (-1)^57 = -1
1.41

23. 1/8
GMAT very often tries to trick you by giving a root linked by addition where it is tempting to simplify the terms - for example: √(25 + 16). It is tempting to think that this will result into 5 + 4 - but you can only simplify roots when the terms ins
12.50%
361
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120

24. 18^2
25
324
= the square root of 9 = 3
625

25. 17^2
12.50%
289
2.449
1.41

26. Examples of roots simplification
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120
√25.16 = √25 . √16 = 5.4 - √50 . √18 = √50.18 = √900 = 30 - √144:16 = √144 : √16 = 12/4 = 3
87.50%
40%

27. what happens when an exponent is negative?
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4
27
25
You cannot simplify this one

28. 6^5
8.33%
...yields a negative result (-1)^57 = -1
7776
You cannot simplify this one

29. 2^6
225
64
144
32

30. 2^5
64
25
32
16.66%

31. (a+b)^2 =
1.41
289
Add the exponents and keep the base 7^3 x 7^5 = 7^8
A^2 + 2ab + b^2

32. A^2-B^2
256
27
20%
(A+B)(A-B)

33. 1/12
75%
8.33%
27
13

34. 3^5
{2 -3 -5 -7 -11 -13 -17 -19 -23 -29 -31 -37 -41 -43 -47 -53 -59 -61 -67 -71 -73 -79 -83 -89 -97}
A^2 + 2ab + b^2
243
7776

35. 1/6
83.33%
16.67%
12.50%
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4

36. 4^5
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3
64
8.33%
1024

37. Simplifying a root
20%
GMAT very often tries to trick you by giving a root linked by addition where it is tempting to simplify the terms - for example: √(25 + 16). It is tempting to think that this will result into 5 + 4 - but you can only simplify roots when the terms ins
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3
4

38. 6^3
1.73
512
216
...yields a negative result (-1)^57 = -1

39. 3^3
...yields a negative result (-1)^57 = -1
27
...yields a positive result (-1)^2 = 1
125

40. 5^3
216
125
512
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120

41. 2^4
16
20%
121
1024

42. Multiples of 12
Multiply the exponents 7^2(^3) = 7^6
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120
...yields a negative result (-1)^57 = -1
A^2 + 2ab + b^2

43. 3^4
A^2 - 2ab + b^2
81
GMAT very often tries to trick you by giving a root linked by addition where it is tempting to simplify the terms - for example: √(25 + 16). It is tempting to think that this will result into 5 + 4 - but you can only simplify roots when the terms ins
324

44. 4^3
16.66%
169
64
50%

45. 1/2
87.50%
50%
5%
...yields a negative result (-1)^57 = -1

46. 13^2
169
(a+b)(a^2-ab+b^2)
256
64

47. 4^4
8
1.41
256
128

48. 2^8
169
256
GMAT very often tries to trick you by giving a root linked by addition where it is tempting to simplify the terms - for example: √(25 + 16). It is tempting to think that this will result into 5 + 4 - but you can only simplify roots when the terms ins
(a+b)(a^2-ab+b^2)

49. to divide powers with the same base...
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3
169
32
7776

50. 19^2
83.33%
361
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120
= the cube root of 8 = 2