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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. (a+b)^2 =
A^2 + 2ab + b^2
7776
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120
2.449

2. 19^2
243
(A+B)(A-B)
1024
361

3. 3/4
...yields a smaller result (1/2)^2 = 1/4
27
12.50%
75%

4. 7/8
27
169
12.50%
87.50%

5. 1/12
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3
1.73
8.33%
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120

6. 1/5
50%
...yields a negative result (-1)^57 = -1
2.449
20%

7. 1/6
20%
√25.16 = √25 . √16 = 5.4 - √50 . √18 = √50.18 = √900 = 30 - √144:16 = √144 : √16 = 12/4 = 3
A^2 + 2ab + b^2
16.67%

8. A^2-B^2
16
169
20%
(A+B)(A-B)

9. 1/6
16.66%
8.33%
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
1296

10. Express 8^1/3 as a radical
(A+B)(A-B)
= the cube root of 8 = 2
...yields a negative result (-1)^57 = -1
...yields a positive result (-1)^2 = 1

11. Express 9^1/2 as a radical
= the square root of 9 = 3
...yields a smaller result (1/2)^2 = 1/4
361
1.73

12. 2^6
16.67%
64
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}

13. √ 3
A^2 + 2ab + b^2
216
1.73
You cannot simplify this one

14. 5^4
32
512
625
25%

15. 2^5
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120
125
32
13

16. to divide powers with the same base...
= the square root of 9 = 3
196
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3
1024

17. 2^7
= the cube root of 8 = 2
2
√25.16 = √25 . √16 = 5.4 - √50 . √18 = √50.18 = √900 = 30 - √144:16 = √144 : √16 = 12/4 = 3
128

18. 2^3
12.50%
324
8
2

19. 14^2
121
8.33%
196
You cannot simplify this one

20. 6^3
50%
8
216
(a-b)(a^2+ab+b^2)

21. Multiples of 12
{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}
50%
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120
32

22. 17^2
64
289
324
2.23

23. 12^2
144
625
13
(a+b)(a^2-ab+b^2)

24. 5^5
3125
324
87.50%
2

25. √ 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}
32
2.449
2.23

26. 3^4
81
12.50%
64
16.66%

27. 4^4
169
256
7776
16.67%

28. Multiples of 15
64
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120
√25.16 = √25 . √16 = 5.4 - √50 . √18 = √50.18 = √900 = 30 - √144:16 = √144 : √16 = 12/4 = 3
1.73

29. 1/8
256
12.50%
216
√25.16 = √25 . √16 = 5.4 - √50 . √18 = √50.18 = √900 = 30 - √144:16 = √144 : √16 = 12/4 = 3

30. Multiples of 8
16.67%
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120
169
2.23

31. 6^5
Subtract the exponents and keep the base the same 4^5/4^2 = 4^3
225
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120
7776

32. Simplifying a root
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120
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
16.67%
256

33. 6^4
25
A^2 - 2ab + b^2
512
1296

34. raising a fraction between zero and 1 to a power...
75%
...yields a smaller result (1/2)^2 = 1/4
8
125

35. 2/5
196
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%
40%

36. a^3-b^3
12 - 24 - 36 - 48 - 60 - 72 - 84 - 96 - 108 - 120
27
(a-b)(a^2+ab+b^2)
32

37. 1/4
1.73
25%
216
...yields a negative result (-1)^57 = -1

38. Prime Numbers between 1 - 100 (total of 25)
128
225
{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

39. what happens when an exponent is negative?
13
Take the reciprocal of the base and change the sign of the exponent (2)^-2 = 1^2/2^2 = 1/4
1.41
A^2 + 2ab + b^2

40. 2^2
A^2 - 2ab + b^2
4
13
12.50%

41. a^3+b^3
121
(a+b)(a^2-ab+b^2)
Add the exponents and keep the base 7^3 x 7^5 = 7^8
{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}

42. 2^10
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120
1024
196
1.41

43. 5/6
1024
= the square root of 9 = 3
83.33%
8 - 16 - 24 - 32 - 40 - 48 - 56 - 64 - 72 - 80 - 88 - 96 - 104 - 112 - 120

44. 2^4
1.73
16
83.33%
256

45. 11^2
324
121
125
64

46. 16^2
(A+B)(A-B)
256
Multiply the exponents 7^2(^3) = 7^6
...yields a positive result (-1)^2 = 1

47. (a-b)^2 =
16
A^2 - 2ab + b^2
15 - 30 - 45 - 60 - 75 - 90 - 105 - 120
2

48. √25+16 = √41
32
You cannot simplify this one
...yields a smaller result (1/2)^2 = 1/4
A^2 + 2ab + b^2

49. to multiple powers (or raise a power to a power)
Multiply the exponents 7^2(^3) = 7^6
16
A^2 + 2ab + b^2
512

50. 1/2
13
1024
16
50%