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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. 2^2
256
4
2
1296

2. √ 2
12.50%
1.41
1.73
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120

3. 5/6
83.33%
128
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120

4. 2^8
1024
256
= the square root of 9 = 3
32

5. a^3-b^3
196
(a-b)(a^2+ab+b^2)
2.449
{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. Multiples of 15
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4
256
27
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120

7. 12^2
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120
7776
144
...yields a positive result (-1)^2 = 1

8. √ 5
40%
2.23
256
625

9. A^2-B^2
32
(A+B)(A-B)
3125
1.73

10. 2/5
40%
289
8
2.449

11. √ 625
125
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120
25
196

12. 2^10
1024
Add the exponents and keep the base 7^3 x 7^5 = 7^8
121
243

13. Express 8^1/3 as a radical
= the cube root of 8 = 2
1024
128
216

14. a negative number raised to an even power...
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
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120
...yields a positive result (-1)^2 = 1

15. 2^4
32
625
169
16

16. 6^5
16.66%
216
2.449
7776

17. 1/20
625
13
216
5%

18. to divide powers with the same base...
(a+b)(a^2-ab+b^2)
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3
A^2 - 2ab + b^2
75%

19. 5^4
(A+B)(A-B)
625
20%
13

20. to multiple powers with the same base...
125
2
Add the exponents and keep the base 7^3 x 7^5 = 7^8
(a+b)(a^2-ab+b^2)

21. raising a fraction between zero and 1 to a power...
144
...yields a smaller result (1/2)^2 = 1/4
2.23
8

22. 15^2
25%
225
1024
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120

23. Prime Numbers between 1 - 100 (total of 25)
Multiply the exponents 7^2(^3) = 7^6
{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}
Add the exponents and keep the base 7^3 x 7^5 = 7^8
256

24. 3/4
...yields a positive result (-1)^2 = 1
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3
75%

25. 2^9
512
...yields a positive result (-1)^2 = 1
256
1024

26. √ 6
40%
20%
2.449
121

27. 2^5
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120
81
32
16

28. 16^2
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120
= the cube root of 8 = 2
A^2 - 2ab + b^2
256

29. (a-b)^2 =
(A+B)(A-B)
3125
A^2 - 2ab + b^2
128

30. 19^2
256
361
1024
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

31. to multiple powers (or raise a power to a power)
289
...yields a positive result (-1)^2 = 1
Multiply the exponents 7^2(^3) = 7^6
A^2 + 2ab + b^2

32. √ 169
2
13
128
40%

33. 18^2
256
25
216
324

34. 5^3
196
2.449
125
4

35. Multiples of 12
289
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120
12.50%
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120

36. 3^4
81
40%
324
20%

37. √ 4
2
...yields a negative result (-1)^57 = -1
225
1024

38. 1/8
144
12.50%
2.23
(A+B)(A-B)

39. 3^3
27
256
361
1296

40. (a+b)^2 =
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^2 + 2ab + b^2
= the cube root of 8 = 2
256

41. √25+16 = √41
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120
27
13
You cannot simplify this one

42. 6^4
125
1296
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3
Multiply the exponents 7^2(^3) = 7^6

43. Examples of roots simplification
√25.16 = √25 . √16 = 5.4 - √50 . √18 = √50.18 = √900 = 30 - √144:16 = √144 : √16 = 12/4 = 3
1024
8.33%
1024

44. 4^5
= the cube root of 8 = 2
3125
4
1024

45. 1/12
8.33%
27
4
625

46. 4^3
2.23
64
7776
225

47. 1/2
512
50%
2.449
16.67%

48. a^3+b^3
16.66%
20%
(a+b)(a^2-ab+b^2)
75%

49. 5^5
40%
3125
A^2 - 2ab + b^2
20%

50. 1/5
20%
You cannot simplify this one
1296
4