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GMAT Quantitative General

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. Think of averages as what? The average of 3 - 4 - 5 - and x is 5. What is x? 3 is 2 less than 5 4 is 1 less than 5 - 5 is the average - x = 5 + 3 = 8
The probability of an event occurring plus the probability of the event not occurring = 1
Exterior angle d is equal to the sum of the two remote interior angles a and b
Balancing
Number is a multiple of 3 and 2

2. 1/8 = what %
12.5%
Gross Profit = Selling Price - Cost
1.7
x - x - x(sq. rt 2)

3. 5/6 = what %
83.3%
D or E
The amount after deductions
Immediately try factoring/simplifying when possible

4. 2n+1 - 2n+3 - 2n+5
4/3 TT r ^3
n! / (n - r)!
Odd
x - x - x(sq. rt 2)

5. Formula for area of a Trapezoid
(sum of bases)(height) / 2
22
16.6%
If the outcome of one event affects the outcome of the other event.

6. Sq. rt(2)
1.4
For a fixed distance - the average speed is inversely related to the amount of time required to make the trip.
Sum of digits is multiple of 9
Sum of digits is multiple of 3

7. 4th rule of Probability
3 - 6 - 9 - 12
Immediately try factoring/simplifying when possible
1 - P(E)
The probability of event A OR B occurring is the probability of event A occurring plus the probability of event B occurring minus the probability of both events occurring. P(A or B) = P(A) +P(B) - P(A and B)

8. Some GMAT word problems involve groups with distinct 'either/or' categories (male/female - blue collar/white collar - etc.) The key is to do what with the information? 1. Find total number of possible outcomes. 2. Find the number of desired outcomes.
Organize into a grid.
gcd(m,n)*lcm(m,n) = mn
(# of favorable outcomes) / (# of possible outcomes)
22

9. Volume of a sphere
Even integer. Neither positive nor negative. Multiple of every number. Not a factor of any number.
Find all prime factors
Minor arc = 2(inscribed angle)
4/3 TT r ^3

10. Trial Problems: look at the probability of NOT OCCURRING
Balancing
3 - 6 - 9 - 12
P(event NOT occurring) = 1 - P(event occurring)
(total distance) / (total time)

11. What to do with equations that have fractions
Find all prime factors
0.15n + 0.08(5) = 0.1(n+5)
12.5%
Immediately try factoring/simplifying when possible

12. Compound interest formula
Sum of digits is multiple of 3 - last two digits multiple of 4.
Last two digits are multiple of 4 or the number can be divided by 2 twice.
Principal (1 + interest/number times compounded)^(t)(n)
Odd

13. How to check whether a number is a multiple of 6
If the outcome of one event affects the outcome of the other event.
$11 - 025
P(E) + P(F) - P(E and F)
Number is a multiple of 3 and 2

14. How to find the slope.
$11 - 025
y2 - y1 / x2 - x1
x - x - x(sq. rt 2)
P(event NOT occurring) = 1 - P(event occurring)

15. To determine the number of integers less than 5000 that are evenly divisible by 15...?
Divide 4999 by 15 => 333 integers
market value
Odd numbers only have ___________
If a point is chosen at random within a space with an area - volume - or length of Y and a space with a respective area - volume - or length of X lies within Y - the probability of choosing a random point within Y is the area - volume - or length of

16. x^r/s = ?
-b +- sq. rt(b^2 - 4ac) / 2a
s Sq. rt (x^r)
Find all prime factors
2 steps

17. Odd and Even rule.
22
Sum of digits is multiple of 3 - last two digits multiple of 4.
Odd numbers only have ___________
Any multiplication involving an even number creates an even product.

18. The average of 5 numbers is 2. After one number is deleted - the new average is -3. What number was deleted?
The amount after deductions
22
1st Rule of Probability: Basic Rule is what?
4/3 TT r ^3

19. How to find all divisors of a number
n! / (n - r)!
(amount of change) / (original amount)
Find all prime factors
(x-n(n)y-n)

20. How to check whether a number is a multiple of 3.
3-4-5 - 5-12-13 - 9-12-15
s Sq. rt (x^r)
Sum of digits is multiple of 3
If the outcome of one event affects the outcome of the other event.

21. 1/6 = what %
The total amount before any deductions
Even
Sum of digits is multiple of 9
16.6%

22. Formula for Mixed Group problems (involving Both/Neither)
Purchase price
(n-1)!
______ |m-n|
Group 1 + Group 2 + Neither - Both = Total

23. Triangle abc with d on the outside with a line. What does d = ?
n! / (n - r)!
The probability of an event occurring plus the probability of the event not occurring = 1
Gross Profit = Selling Price - Cost
Exterior angle d is equal to the sum of the two remote interior angles a and b

24. Always try to factor
(sum of bases)(height) / 2
P(E)P(F)
always try to factor
Minor arc = 2(inscribed angle)

25. Gross Profit formula
A = P(1 + r) ^n
Gross Profit = Selling Price - Cost
The amount after deductions
To find the number of distinct permutations of a set of items with indistinguishable ('repeat') items - divide the factorial of the items in the set by the product of the factorials of the number of indistinguishable elements.

26. (1/4)^2
1/16
To find the number of distinct permutations of a set of items with indistinguishable ('repeat') items - divide the factorial of the items in the set by the product of the factorials of the number of indistinguishable elements.
Group 1 + Group 2 + Neither - Both = Total
Total = mean x (number of terms) Number deleted = (original total) - (new total) Number added = (new total) - (original total)

27. Number of integers from A to B inclusive = B - A + 1 - How many consecutive integers are there from 73 through 419 - inclusive?
2 steps
multiply or divide the numbers outside the radical signs - then the numbers inside the radical signs
1.4
347

28. gcd(m,n)
multiply or divide the numbers outside the radical signs - then the numbers inside the radical signs
4/3 TT r ^3
______ |m-n|
Even integer. Neither positive nor negative. Multiple of every number. Not a factor of any number.

29. The average of consecutive numbers
gcd(m,n)*lcm(m,n) = mn
______ |m-n|
The average of a set of evenly spaced consecutive numbers is the average of the smallest and largest numbers in the set.
14 liters

30. Work problem rule
(sum of bases)(height) / 2
2 steps
(x-n(n)y-n)
Consider work done in one hour. Inverse of the time it takes everyone working together = Sum of the inverse of the times it would take each person working individually.

31. Percent Formula
Number is a multiple of 3 and 2
(amount of change) / (original amount)
16.6%
p/100 = is/of

32. Circular permutation: The number of ways to arrange n distinct objects along a fixed circle is?
x - x - x(sq. rt 2)
1. Start by writing each number as a product of primes. 2. Write so that each new prime factor begins in the same place. 3. Lowest common multiple is found by multiplying all factors in either list.
(n-1)!
Even

33. Gross
Balancing
The total amount before any deductions
Minor arc = 2(inscribed angle)
The number of ways independent events can occur together can be determined by multiplying together the number of possible outcomes for each event.

34. 3rd Rule of Probability: Conditional Probability
market value
x - x - x(sq. rt 2)
the probability of event A AND event B occurring is the probability of event A times the probability of event B - given that A has already occurred.
| A union B| = |A| + |B| - |A intersect B|

35. If $10 -000 is invested at 10% annual interest - compounded semi-annually - what is the balance after 1 year?
$11 - 025
The number of ways independent events can occur together can be determined by multiplying together the number of possible outcomes for each event.
D or E
The average of a set of evenly spaced consecutive numbers is the average of the smallest and largest numbers in the set.

36. Dependent events: When are two events said to be dependent events?
The average of a set of evenly spaced consecutive numbers is the average of the smallest and largest numbers in the set.
Last two digits are multiple of 4 or the number can be divided by 2 twice.
The amount after deductions
If the outcome of one event affects the outcome of the other event.

37. 2nd Rule of Probability: P(E) = 1 - P(not E)
at least 3 steps
The probability of an event occurring plus the probability of the event not occurring = 1
Group 1 + Group 2 + Neither - Both = Total
D or E

38. Combined Events: Not E = P(not E) = ?
1 - P(E)
4/3 TT r ^3
Group 1 + Group 2 + Neither - Both = Total
The average of a set of evenly spaced consecutive numbers is the average of the smallest and largest numbers in the set.

39. Net
Divide 4999 by 15 => 333 integers
n! / (n - r)!
3-4-5 - 5-12-13 - 9-12-15
The amount after deductions

40. How do you multiply roots together.
(sum of bases)(height) / 2
1st Rule of Probability: Basic Rule is what?
multiply or divide the numbers outside the radical signs - then the numbers inside the radical signs
x(sq. rt 3) - x - 2x

41. Odd Factors
P(E) + P(F) - P(E and F)
Odd numbers only have ___________
y2 - y1 / x2 - x1
Sum of digits is multiple of 9

42. The number of outcomes that result in A divided by the total number of possible outcomes.
The probability of an event occurring plus the probability of the event not occurring = 1
s Sq. rt (x^r)
Even integer. Neither positive nor negative. Multiple of every number. Not a factor of any number.
The probability of event occurring is...

43. Three triangle length patterns
Sum of digits is multiple of 3
Gross Profit = Selling Price - Cost
3-4-5 - 5-12-13 - 9-12-15
Sum of digits is multiple of 3 - last two digits multiple of 4.

44. How to check whether number is multiple of 9
market value
Sum of digits is multiple of 9
1 - P(E)
The probability of an event occurring plus the probability of the event not occurring = 1

45. Intersecting Sets
| A union B| = |A| + |B| - |A intersect B|
P(E)P(F)
1.7
1. Start by writing each number as product of primes. 2. Write so that each new prime factor begins in the same place. 3. Greatest Common Factor is found by multiplying all factors appearing in BOTH lists

46. How to check whether a number is a multiple of 4.
Last two digits are multiple of 4 or the number can be divided by 2 twice.
______ |m-n|
The number of ways independent events can occur together can be determined by multiplying together the number of possible outcomes for each event.
gcd(m,n)*lcm(m,n) = mn

47. Multiplication principle
y2 - y1 / x2 - x1
if a first object may be chosen in m ways and a second object may be chosen in n ways - then there are mn ways of choosing both objects
(# of favorable outcomes) / (# of possible outcomes)
The total amount before any deductions

48. Average Rate: Average speed
market value
Consider work done in one hour. Inverse of the time it takes everyone working together = Sum of the inverse of the times it would take each person working individually.
(total distance) / (total time)
the probability of event A AND event B occurring is the probability of event A times the probability of event B - given that A has already occurred.

49. Simple probability
Last two digits are multiple of 4 or the number can be divided by 2 twice.
(# of favorable outcomes) / (# of possible outcomes)
1 - P(E)
s Sq. rt (x^r)

50. Inscribed Angle - Minor Arc
The total amount before any deductions
3-4-5 - 5-12-13 - 9-12-15
Minor arc = 2(inscribed angle)
______ |m-n|