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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. 2^9
You cannot simplify this one
1296
512
196

2. 16^2
4
256
81
(a-b)(a^2+ab+b^2)

3. a^3-b^3
(a-b)(a^2+ab+b^2)
243
5%
4

4. 5/6
27
2.23
A^2 + 2ab + b^2
83.33%

5. 3^4
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120
81
1024
{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}

6. √ 2
1.41
64
= the cube root of 8 = 2
13

7. 1/12
121
625
324
8.33%

8. 17^2
2
289
20%
16

9. a negative number raised to an even power...
...yields a positive result (-1)^2 = 1
13
= the cube root of 8 = 2
1296

10. 12^2
32
144
...yields a negative result (-1)^57 = -1
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4

11. to divide powers with the same base...
12.50%
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120
8
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3

12. 1/4
(a+b)(a^2-ab+b^2)
25%
1024
2.449

13. √ 4
{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}
2
256
12.50%

14. 6^4
27
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120
1296
144

15. 14^2
87.50%
225
196
121

16. Examples of roots simplification
32
Add the exponents and keep the base 7^3 x 7^5 = 7^8
225
√25.16 = √25 . √16 = 5.4 - √50 . √18 = √50.18 = √900 = 30 - √144:16 = √144 : √16 = 12/4 = 3

17. 1/6
16.66%
16.67%
8.33%
...yields a positive result (-1)^2 = 1

18. 3/4
A^2 - 2ab + b^2
75%
2.449
196

19. 15^2
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120
16
225
Multiply the exponents 7^2(^3) = 7^6

20. 4^5
12.50%
...yields a negative result (-1)^57 = -1
1024
87.50%

21. 18^2
12.50%
324
8.33%
A^2 + 2ab + b^2

22. Multiples of 8
2.23
{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}
50%
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120

23. 2^3
625
(a+b)(a^2-ab+b^2)
8
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4

24. 2^2
(A+B)(A-B)
225
4
144

25. Express 9^1/2 as a radical
144
(a+b)(a^2-ab+b^2)
20%
= the square root of 9 = 3

26. a negative number raised to an odd power...
8.33%
75%
128
...yields a negative result (-1)^57 = -1

27. 1/5
8
20%
81
27

28. Prime Numbers between 1 - 100 (total of 25)
256
= the cube root of 8 = 2
625
{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}

29. 1/8
361
2.449
27
12.50%

30. 5^4
625
75%
289
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4

31. 2^6
50%
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120
64
(A+B)(A-B)

32. a^3+b^3
7776
(a+b)(a^2-ab+b^2)
...yields a negative result (-1)^57 = -1
256

33. 6^5
7776
1.73
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3
5%

34. 2^5
16.66%
32
625
361

35. √25+16 = √41
225
You cannot simplify this one
512
√25.16 = √25 . √16 = 5.4 - √50 . √18 = √50.18 = √900 = 30 - √144:16 = √144 : √16 = 12/4 = 3

36. 19^2
256
361
125
...yields a smaller result (1/2)^2 = 1/4

37. 11^2
16
324
121
= the square root of 9 = 3

38. Multiples of 15
{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}
16.66%
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120
16

39. √ 6
40%
16.66%
(a+b)(a^2-ab+b^2)
2.449

40. 5^5
2.23
87.50%
3125
13

41. √ 3
...yields a negative result (-1)^57 = -1
1.73
√25.16 = √25 . √16 = 5.4 - √50 . √18 = √50.18 = √900 = 30 - √144:16 = √144 : √16 = 12/4 = 3
16.67%

42. 2^8
243
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4
1024
256

43. to multiple powers (or raise a power to a power)
Multiply the exponents 7^2(^3) = 7^6
4
121
A^2 + 2ab + b^2

44. 7/8
87.50%
20%
75%
8.33%

45. √ 625
25
512
1296
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120

46. Multiples of 12
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120
...yields a negative result (-1)^57 = -1
(a+b)(a^2-ab+b^2)
25%

47. 2^4
1024
16
25%
A^2 - 2ab + b^2

48. 3^3
4
361
27
2.23

49. what happens when an exponent is negative?
16.66%
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4
225
1.41

50. 4^3
...yields a negative result (-1)^57 = -1
5%
64
1296