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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. Average Rate: Average A per B
Sum of digits is multiple of 3 - last two digits multiple of 4.
(total A) / (total B)
For a fixed distance - the average speed is inversely related to the amount of time required to make the trip.
gcd(m,n)*lcm(m,n) = mn

2. 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 event A AND event B occurring is the probability of event A times the probability of event B - given that A has already occurred.
Balancing
(total A) / (total B)
12^3

3. Percent Formula
D or E
22
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.
p/100 = is/of

4. 3^3 x 4^3 = ?
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
12^3
-b +- sq. rt(b^2 - 4ac) / 2a
12.5%

5. Inscribed Angle - Minor Arc
Minor arc = 2(inscribed angle)
Sum of digits is multiple of 9
The total amount before any deductions
Principal (1 + interest/number times compounded)^(t)(n)

6. x^r/s = ?
3-4-5 - 5-12-13 - 9-12-15
If the outcome of one event affects the outcome of the other event.
P(E) + P(F) - P(E and F)
s Sq. rt (x^r)

7. If you have to guess in a problem - which ones should you guess? Especially if you have to plug numbers.
Immediately UNFACTOR or vice versa
12.5%
D or E
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

8. 4th rule of Probability
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
1st Rule of Probability: Basic Rule is what?
1.4
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)

9. Multiples of 3
3 - 6 - 9 - 12
3-4-5 - 5-12-13 - 9-12-15
Divide 4999 by 15 => 333 integers
______ |m-n|

10. Sum of consecutive numbers
Exterior angle d is equal to the sum of the two remote interior angles a and b
Even
sum = (average)(number of terms)
$11 - 025

11. Price sold for by retailer (after markup)
(total A) / (total B)
-b +- sq. rt(b^2 - 4ac) / 2a
market value
s Sq. rt (x^r)

12. 1/8 = what %
n! / (n - r)!
Principal (1 + interest/number times compounded)^(t)(n)
Organize into a grid.
12.5%

13. 2n+1 - 2n+3 - 2n+5
Find simple interest then look for the answer that is a little bigger
Odd
For a fixed distance - the average speed is inversely related to the amount of time required to make the trip.
1.4

14. 3rd Rule of Probability: Conditional Probability
Sum of digits is multiple of 9
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.
Sum of digits is multiple of 3
Exterior angle d is equal to the sum of the two remote interior angles a and b

15. How to check whether a number is a multiple of 6
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.
at least 3 steps
Number is a multiple of 3 and 2
Figure out the probability for each individual event. Multiply the individual probabilities together.

16. How to check whether a number is a multiple of 3.
Sum of digits is multiple of 3
1 - P(E)
The probability of an event occurring plus the probability of the event not occurring = 1
(x-n(n)y-n)

17. Simple probability
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
180(n-2)
The total amount before any deductions
(# of favorable outcomes) / (# of possible outcomes)

18. The average of 5 numbers is 2. After one number is deleted - the new average is -3. What number was deleted?
1 - P(E)
(# of favorable outcomes) / (# of possible outcomes)
22
Sum of digits is multiple of 9

19. 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.
n! / (n - r)!
p/100 = is/of
Organize into a grid.
1.7

20. Triangle abc with d on the outside with a line. What does d = ?
If the outcome of one event affects the outcome of the other event.
Purchase price
Exterior angle d is equal to the sum of the two remote interior angles a and b
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

21. 2nd Rule of Probability: P(E) = 1 - P(not E)
The probability of an event occurring plus the probability of the event not occurring = 1
180(n-2)
1st Rule of Probability: Basic Rule is what?
1

22. Formula for area of a Trapezoid
16.6%
(x-n(n)y-n)
Purchase price
(sum of bases)(height) / 2

23. How to check whether a number is a multiple of 12.
Sum of digits is multiple of 3 - last two digits multiple of 4.
sum = (average)(number of terms)
-b +- sq. rt(b^2 - 4ac) / 2a
The total amount before any deductions

24. Simple Interest Formula (remember this is the total amount of money in the bank after the interest is earned)
D or E
Divide 4999 by 15 => 333 integers
P(E)P(F)
A = P(1 + r) ^n

25. 2n - 2n+2 - 2n+4
Odd numbers only have ___________
Even
Check each prime number up to the approximate square root of the number. If you haven't found a number less than or equal to the square root of the number - then the number is prime.
(n-1)!

26. Circular permutation: The number of ways to arrange n distinct objects along a fixed circle is?
Purchase price
(n-1)!
x(sq. rt 3) - x - 2x
(total A) / (total B)

27. Percent increase = ?
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.
1 - P(E)
market value
(amount of change) / (original amount)

28. Number of integers from A to B inclusive = B - A + 1 - How many consecutive integers are there from 73 through 419 - inclusive?
1.4
Divide 4999 by 15 => 333 integers
347
(n-1)!

29. Gross
2 steps
Exterior angle d is equal to the sum of the two remote interior angles a and b
The total amount before any deductions
Sum of digits is multiple of 9

30. gcd(m,n)
-b +- sq. rt(b^2 - 4ac) / 2a
180(n-2)
______ |m-n|
always try to factor

31. The number of ways independent events can occur together.
principle (interest rate - in decimal form) (time - in years)
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.
The number of ways independent events can occur together can be determined by multiplying together the number of possible outcomes for each event.
The average of a set of evenly spaced consecutive numbers is the average of the smallest and largest numbers in the set.

32. Odd Factors
P(E) + P(F) - P(E and F)
Immediately try factoring/simplifying when possible
P(event NOT occurring) = 1 - P(event occurring)
Odd numbers only have ___________

33. 5/6 = what %
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)
Figure out the probability for each individual event. Multiply the individual probabilities together.
1.4
83.3%

34. Compound interest formula
Find all prime factors
Sum of digits is multiple of 9
P(E)P(F)
Principal (1 + interest/number times compounded)^(t)(n)

35. Set Problems formula
Organize into a grid.
at least 3 steps
(total distance) / (total time)
(x-n(n)y-n)

36. 0! = ?
4/3 TT r ^3
Number is a multiple of 3 and 2
Find all prime factors
1

37. Compound interest rule
Find simple interest then look for the answer that is a little bigger
83.3%
1st Rule of Probability: Basic Rule is what?
If the outcome of one event affects the outcome of the other event.

38. To determine the number of integers less than 5000 that are evenly divisible by 15...?
s Sq. rt (x^r)
$11 - 025
Divide 4999 by 15 => 333 integers
83.3%

39. Price purchased for by wholesaler
Purchase price
4/3 TT r ^3
Sum of digits is multiple of 3
347

40. How to find all divisors of a number
______ |m-n|
14 liters
Find all prime factors
n! / (n - r)!

41. 45-45-90 triangle basic lengths of sides
(x-n(n)y-n)
Exterior angle d is equal to the sum of the two remote interior angles a and b
Organize into a grid.
x - x - x(sq. rt 2)

42. Three triangle length patterns
3-4-5 - 5-12-13 - 9-12-15
Odd
0.15n + 0.08(5) = 0.1(n+5)
Even integer. Neither positive nor negative. Multiple of every number. Not a factor of any number.

43. Lowest Common Multiple 60: 2 x 2 x 3 x 5 - 72: 2 x 2 x 2 x 3 x 3 - LCM: 2 x 2 x 2 x 3 x 3 x 5
(n-1)!
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)
Number is a multiple of 3 and 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.

44. Permutations: Order Matters
n! / (n - r)!
Gross Profit = Selling Price - Cost
always try to factor
Immediately UNFACTOR or vice versa

45. What to do with equations that have fractions
| A union B| = |A| + |B| - |A intersect B|
Any multiplication involving an even number creates an even product.
Immediately try factoring/simplifying when possible
1 - P(E)

46. Average Rate: Average speed
(total distance) / (total time)
If the outcome of one event affects the outcome of the other event.
A = P(1 + r) ^n
(x-n(n)y-n)

47. When you see an equation in factored form in a question?
Immediately UNFACTOR or vice versa
(total A) / (total B)
x(sq. rt 3) - x - 2x
principle (interest rate - in decimal form) (time - in years)

48. In general - medium questions require how many steps to solve?
Odd
Principal (1 + interest/number times compounded)^(t)(n)
2 steps
principle (interest rate - in decimal form) (time - in years)

49. Dependent events: When are two events said to be dependent events?
Check each prime number up to the approximate square root of the number. If you haven't found a number less than or equal to the square root of the number - then the number is prime.
y2 - y1 / x2 - x1
If the outcome of one event affects the outcome of the other event.
Organize into a grid.

50. Probability and Geometry.
$11 - 025
Check each prime number up to the approximate square root of the number. If you haven't found a number less than or equal to the square root of the number - then the number is prime.
A = P(1 + r) ^n
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