Test your basic knowledge |

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. Multiples of 15
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120
Add the exponents and keep the base 7^3 x 7^5 = 7^8
12.50%
You cannot simplify this one

2. 3/4
75%
1024
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120

3. 13^2
64
You cannot simplify this one
169
256

4. 6^4
7776
1296
40%
25%

5. 4^3
64
225
196
256

6. raising a fraction between zero and 1 to a power...
7776
...yields a smaller result (1/2)^2 = 1/4
2
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120

7. 12^2
75%
256
144
83.33%

8. √ 625
25
16.66%
50%
361

9. Multiples of 8
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120
You cannot simplify this one
216
= the square root of 9 = 3

10. √ 5
Multiply the exponents 7^2(^3) = 7^6
2.23
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3
A^2 - 2ab + b^2

11. 17^2
289
√25.16 = √25 . √16 = 5.4 - √50 . √18 = √50.18 = √900 = 30 - √144:16 = √144 : √16 = 12/4 = 3
7776
125

12. a negative number raised to an odd power...
2
...yields a negative result (-1)^57 = -1
1024
16.67%

13. to divide powers with the same base...
81
512
5%
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3

14. 2^2
4
16.67%
225
12.50%

15. 1/8
27
2.449
87.50%
12.50%

16. 19^2
...yields a smaller result (1/2)^2 = 1/4
{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}
1.73
361

17. 2^5
4
16.67%
32
243

18. 5^3
(a+b)(a^2-ab+b^2)
125
3125
256

19. 2^7
(a-b)(a^2+ab+b^2)
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4
81
128

20. 7/8
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3
87.50%
1.41
64

21. (a-b)^2 =
256
A^2 - 2ab + b^2
25%
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120

22. a negative number raised to an even power...
...yields a positive result (-1)^2 = 1
324
512
243

23. 2^8
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3
324
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

24. 1/5
243
20%
= the square root of 9 = 3
...yields a negative result (-1)^57 = -1

25. A^2-B^2
(a+b)(a^2-ab+b^2)
(A+B)(A-B)
1.73
64

26. 1/20
289
5%
16
A^2 - 2ab + b^2

27. √ 169
13
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120
...yields a smaller result (1/2)^2 = 1/4
40%

28. Prime Numbers between 1 - 100 (total of 25)
225
= the square root of 9 = 3
{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}
40%

29. to multiple powers with the same base...
144
25%
361
Add the exponents and keep the base 7^3 x 7^5 = 7^8

30. √ 4
25
2
196
225

31. 2^10
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4
196
2
1024

32. 16^2
16.67%
256
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}

33. 3^3
16
...yields a smaller result (1/2)^2 = 1/4
75%
27

34. 2^3
169
8
216
You cannot simplify this one

35. 11^2
121
{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+B)(A-B)
= the square root of 9 = 3

36. 5^5
83.33%
3125
128
289

37. √ 2
1024
121
1.41
64

38. 6^5
1296
7776
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120
50%

39. 1/2
50%
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120
16.66%
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120

40. 18^2
216
625
1.41
324

41. 3^5
= the square root of 9 = 3
243
1024
64

42. 3^4
13
81
225
(a-b)(a^2+ab+b^2)

43. 2/5
You cannot simplify this one
144
Add the exponents and keep the base 7^3 x 7^5 = 7^8
40%

44. Simplifying a root
A^2 - 2ab + b^2
87.50%
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)

45. 4^4
256
32
(a-b)(a^2+ab+b^2)
40%

46. 1/6
196
A^2 + 2ab + b^2
16.66%
243

47. Express 9^1/2 as a radical
= the cube root of 8 = 2
196
= the square root of 9 = 3
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

48. 15^2
12.50%
225
50%
1.41

49. Multiples of 12
125
121
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120
1296

50. (a+b)^2 =
1024
8.33%
2.23
A^2 + 2ab + b^2