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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. to multiple powers (or raise a power to a power)
50%
1.73
Multiply the exponents 7^2(^3) = 7^6
8.33%

2. √ 6
16.66%
Add the exponents and keep the base 7^3 x 7^5 = 7^8
2.449
83.33%

3. Multiples of 12
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120
1296
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4
1.41

4. 3^4
2.449
Multiply the exponents 7^2(^3) = 7^6
27
81

5. 1/12
8.33%
5%
12.50%
289

6. Prime Numbers between 1 - 100 (total of 25)
225
50%
{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}
16.67%

7. 6^3
216
12.50%
125
16.67%

8. 11^2
81
121
1.41
196

9. Express 9^1/2 as a radical
1296
= the cube root of 8 = 2
625
= the square root of 9 = 3

10. 4^4
2.23
256
= the square root of 9 = 3
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120

11. √25+16 = √41
= the square root of 9 = 3
64
You cannot simplify this one
...yields a negative result (-1)^57 = -1

12. 5^5
256
40%
{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}
3125

13. 7/8
Add the exponents and keep the base 7^3 x 7^5 = 7^8
169
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120
87.50%

14. Express 8^1/3 as a radical
= the cube root of 8 = 2
4
(a-b)(a^2+ab+b^2)
16.66%

15. 5^4
125
27
625
87.50%

16. 1/2
7776
50%
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4
4

17. 2^10
2
1024
20%
16.67%

18. Multiples of 15
256
A^2 + 2ab + b^2
5%
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120

19. raising a fraction between zero and 1 to a power...
...yields a smaller result (1/2)^2 = 1/4
5%
16.67%
16.66%

20. a^3+b^3
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120
121
625
(a+b)(a^2-ab+b^2)

21. 15^2
A^2 - 2ab + b^2
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3
225
196

22. 2^6
...yields a positive result (-1)^2 = 1
64
16.66%
256

23. 2^7
361
1024
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120
128

24. Multiples of 8
75%
3125
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120
27

25. 2^5
16
32
40%
27

26. 3^5
Multiply the exponents 7^2(^3) = 7^6
1024
243
...yields a smaller result (1/2)^2 = 1/4

27. 19^2
361
(a-b)(a^2+ab+b^2)
(a+b)(a^2-ab+b^2)
8

28. √ 3
196
1.73
256
12.50%

29. 18^2
75%
128
243
324

30. (a+b)^2 =
144
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4
16.67%
A^2 + 2ab + b^2

31. 16^2
256
16.67%
(a-b)(a^2+ab+b^2)
2

32. a negative number raised to an odd power...
256
...yields a negative result (-1)^57 = -1
7776
225

33. 2/5
196
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3
7776
40%

34. 1/8
128
√25.16 = √25 . √16 = 5.4 - √50 . √18 = √50.18 = √900 = 30 - √144:16 = √144 : √16 = 12/4 = 3
12.50%
81

35. 1/5
625
5%
1.73
20%

36. 17^2
289
361
256
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120

37. 2^8
You cannot simplify this one
256
4
1.41

38. 5/6
83.33%
{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}
216
256

39. 4^5
75%
1024
(A+B)(A-B)
125

40. 13^2
216
289
169
2.449

41. 5^3
2.23
...yields a smaller result (1/2)^2 = 1/4
A^2 - 2ab + b^2
125

42. 1/20
243
= the cube root of 8 = 2
5%
Multiply the exponents 7^2(^3) = 7^6

43. Simplifying a root
125
1296
(A+B)(A-B)
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

44. 14^2
361
50%
196
225

45. 3/4
121
(a-b)(a^2+ab+b^2)
289
75%

46. 1/4
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4
144
Multiply the exponents 7^2(^3) = 7^6
25%

47. (a-b)^2 =
...yields a negative result (-1)^57 = -1
A^2 - 2ab + b^2
1296
625

48. 4^3
20%
{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}
64
7776

49. 3^3
25%
27
1024
Add the exponents and keep the base 7^3 x 7^5 = 7^8

50. a negative number raised to an even power...
...yields a positive result (-1)^2 = 1
(a-b)(a^2+ab+b^2)
4
8.33%