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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. Examples of roots simplification
216
√25.16 = √25 . √16 = 5.4 - √50 . √18 = √50.18 = √900 = 30 - √144:16 = √144 : √16 = 12/4 = 3
...yields a negative result (-1)^57 = -1
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120

2. √ 5
2.23
27
196
...yields a positive result (-1)^2 = 1

3. a^3+b^3
(a+b)(a^2-ab+b^2)
144
225
1.73

4. Multiples of 12
64
4
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120
You cannot simplify this one

5. 14^2
4
2
196
87.50%

6. 1/6
16.66%
256
A^2 + 2ab + b^2
32

7. (a+b)^2 =
2.23
Add the exponents and keep the base 7^3 x 7^5 = 7^8
A^2 + 2ab + b^2
7776

8. a negative number raised to an even power...
...yields a negative result (-1)^57 = -1
...yields a positive result (-1)^2 = 1
3125
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120

9. 5^4
2.449
625
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120
You cannot simplify this one

10. √ 3
...yields a smaller result (1/2)^2 = 1/4
1.73
2
1296

11. 1/6
= the cube root of 8 = 2
2
16.67%
Multiply the exponents 7^2(^3) = 7^6

12. 11^2
121
(A+B)(A-B)
1024
...yields a negative result (-1)^57 = -1

13. what happens when an exponent is negative?
50%
12.50%
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4
3125

14. √ 625
25
40%
83.33%
121

15. 13^2
40%
20%
√25.16 = √25 . √16 = 5.4 - √50 . √18 = √50.18 = √900 = 30 - √144:16 = √144 : √16 = 12/4 = 3
169

16. 18^2
324
40%
5%
12.50%

17. √ 4
2
81
20%
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120

18. 6^3
121
125
(A+B)(A-B)
216

19. A^2-B^2
A^2 - 2ab + b^2
(A+B)(A-B)
625
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

20. 2^6
= the square root of 9 = 3
8
75%
64

21. 4^3
Add the exponents and keep the base 7^3 x 7^5 = 7^8
40%
64
16.67%

22. a^3-b^3
(a-b)(a^2+ab+b^2)
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120
32
Add the exponents and keep the base 7^3 x 7^5 = 7^8

23. Prime Numbers between 1 - 100 (total of 25)
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}
= the square root of 9 = 3
16.67%

24. to multiple powers with the same base...
32
Add the exponents and keep the base 7^3 x 7^5 = 7^8
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3
75%

25. raising a fraction between zero and 1 to a power...
25
...yields a smaller result (1/2)^2 = 1/4
4
Add the exponents and keep the base 7^3 x 7^5 = 7^8

26. 3^4
144
4
2.23
81

27. 5/6
(a-b)(a^2+ab+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
512
83.33%

28. 3^3
20%
3125
27
1.73

29. 2^9
= the cube root of 8 = 2
2.23
Add the exponents and keep the base 7^3 x 7^5 = 7^8
512

30. 7/8
25
You cannot simplify this one
25%
87.50%

31. 2^4
16
8.33%
75%
16.67%

32. 2^7
128
75%
Add the exponents and keep the base 7^3 x 7^5 = 7^8
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120

33. √ 169
13
1296
(a+b)(a^2-ab+b^2)
16

34. 16^2
144
121
1024
256

35. 2^2
25%
4
169
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3

36. √25+16 = √41
32
Multiply the exponents 7^2(^3) = 7^6
You cannot simplify this one
= the square root of 9 = 3

37. 17^2
75%
Add the exponents and keep the base 7^3 x 7^5 = 7^8
289
81

38. to multiple powers (or raise a power to a power)
4
Multiply the exponents 7^2(^3) = 7^6
7776
256

39. 1/12
512
(a-b)(a^2+ab+b^2)
25%
8.33%

40. 2^8
75%
256
7776
27

41. 2^3
196
8
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

42. 19^2
25%
...yields a smaller result (1/2)^2 = 1/4
361
20%

43. √ 6
2.449
1296
1.73
225

44. Express 8^1/3 as a radical
125
256
= the cube root of 8 = 2
...yields a smaller result (1/2)^2 = 1/4

45. 3^5
243
= the square root of 9 = 3
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120
2.449

46. 1/5
16.66%
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4
20%
25

47. 2^10
1024
2.449
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4
...yields a smaller result (1/2)^2 = 1/4

48. 6^5
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4
25%
= the cube root of 8 = 2
7776

49. 12^2
81
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
144

50. 15^2
225
125
You cannot simplify this one
289