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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. 4^4
20%
256
13
Multiply the exponents 7^2(^3) = 7^6

2. 4^3
2.449
25%
64
256

3. A^2-B^2
256
2.23
(A+B)(A-B)
A^2 + 2ab + b^2

4. (a+b)^2 =
1024
A^2 + 2ab + b^2
2
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3

5. Multiples of 12
25%
...yields a positive result (-1)^2 = 1
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120
64

6. 5^5
3125
361
289
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120

7. √ 5
25
{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}
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4
2.23

8. 12^2
256
144
1.73
= the cube root of 8 = 2

9. 7/8
87.50%
Multiply the exponents 7^2(^3) = 7^6
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
50%

10. 6^5
7776
83.33%
625
125

11. to multiple powers with the same base...
Multiply the exponents 7^2(^3) = 7^6
Add the exponents and keep the base 7^3 x 7^5 = 7^8
= the cube root of 8 = 2
50%

12. 3^3
243
27
1.41
1024

13. raising a fraction between zero and 1 to a power...
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120
...yields a smaller result (1/2)^2 = 1/4
40%
...yields a positive result (-1)^2 = 1

14. 16^2
32
16.66%
13
256

15. 2/5
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120
256
= the cube root of 8 = 2
40%

16. 2^6
64
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3
16.67%
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120

17. Simplifying a root
...yields a smaller result (1/2)^2 = 1/4
243
216
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

18. 1/12
8.33%
144
12.50%
2

19. 15^2
125
225
You cannot simplify this one
256

20. 17^2
3125
256
121
289

21. √ 2
64
25%
3125
1.41

22. a negative number raised to an odd power...
7776
You cannot simplify this one
(a+b)(a^2-ab+b^2)
...yields a negative result (-1)^57 = -1

23. √ 6
2.449
5%
...yields a positive result (-1)^2 = 1
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120

24. √ 4
25%
(a+b)(a^2-ab+b^2)
2
1296

25. 1/5
20%
You cannot simplify this one
256
75%

26. 2^2
Multiply the exponents 7^2(^3) = 7^6
8.33%
1024
4

27. 6^3
5%
243
216
25

28. 5^4
4
8
625
1296

29. √25+16 = √41
...yields a smaller result (1/2)^2 = 1/4
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120
20%
You cannot simplify this one

30. Express 9^1/2 as a radical
40%
64
2.449
= the square root of 9 = 3

31. Examples of roots simplification
...yields a smaller result (1/2)^2 = 1/4
1296
√25.16 = √25 . √16 = 5.4 - √50 . √18 = √50.18 = √900 = 30 - √144:16 = √144 : √16 = 12/4 = 3
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120

32. to multiple powers (or raise a power to a power)
Multiply the exponents 7^2(^3) = 7^6
40%
7776
324

33. a^3-b^3
(A+B)(A-B)
(a-b)(a^2+ab+b^2)
243
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120

34. 6^4
64
83.33%
1024
1296

35. Multiples of 15
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120
12.50%
...yields a negative result (-1)^57 = -1
144

36. (a-b)^2 =
87.50%
A^2 - 2ab + b^2
196
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120

37. 1/8
1.41
12.50%
A^2 - 2ab + b^2
243

38. Prime Numbers between 1 - 100 (total of 25)
{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%
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4
40%

39. 18^2
324
16.66%
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120
Add the exponents and keep the base 7^3 x 7^5 = 7^8

40. 13^2
216
361
169
196

41. 14^2
1024
196
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120
64

42. √ 169
196
64
13
27

43. 11^2
121
27
8
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4

44. 1/2
You cannot simplify this one
50%
216
32

45. Multiples of 8
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120
256
1.41
75%

46. 2^5
32
3125
A^2 - 2ab + b^2
87.50%

47. 2^10
2.23
1024
A^2 + 2ab + b^2
...yields a smaller result (1/2)^2 = 1/4

48. 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
225
83.33%
...yields a positive result (-1)^2 = 1

49. 3^5
...yields a negative result (-1)^57 = -1
324
243
225

50. to divide powers with the same base...
121
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3
= the square root of 9 = 3
(a+b)(a^2-ab+b^2)