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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. Compound interest formula
Principal (1 + interest/number times compounded)^(t)(n)
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.
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.
Find all prime factors

2. What does the Sum of the angles in a Regular Polygon formula look like?
Exterior angle d is equal to the sum of the two remote interior angles a and b
2 steps
(x-n(n)y-n)
180(n-2)

3. 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
Sum of digits is multiple of 3
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
1/16
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.

4. Properties of 0
For a fixed distance - the average speed is inversely related to the amount of time required to make the trip.
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.
Even integer. Neither positive nor negative. Multiple of every number. Not a factor of any number.
Sum of digits is multiple of 9

5. 2nd Rule of Probability: P(E) = 1 - P(not E)
0.15n + 0.08(5) = 0.1(n+5)
principle (interest rate - in decimal form) (time - in years)
Purchase price
The probability of an event occurring plus the probability of the event not occurring = 1

6. Dependent events: When are two events said to be dependent events?
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.
1.7
Sum of digits is multiple of 3
If the outcome of one event affects the outcome of the other event.

7. gcd(m,n)*lcm(m,n)
Immediately try factoring/simplifying when possible
(total distance) / (total time)
gcd(m,n)*lcm(m,n) = mn
Sum of digits is multiple of 9

8. How to check whether a number is a multiple of 3.
16.6%
Divide 4999 by 15 => 333 integers
Sum of digits is multiple of 3
12.5%

9. Indistinguishable events how to find the number of permutations

10. 3rd Rule of Probability: Conditional Probability
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.
Figure out the probability for each individual event. Multiply the individual probabilities together.
(amount of change) / (original amount)
Minor arc = 2(inscribed angle)

11. How do you multiply roots together.
______ |m-n|
at least 3 steps
sum = (average)(number of terms)
multiply or divide the numbers outside the radical signs - then the numbers inside the radical signs

12. 2n - 2n+2 - 2n+4
Organize into a grid.
2 steps
Odd
Even

13. Set Problems formula
Balancing
(total distance) / (total time)
(x-n(n)y-n)
3 - 6 - 9 - 12

14. Average Rate: Average A per B
22
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
(total A) / (total B)
2 steps

15. Sq. rt(2)
1.4
Gross Profit = Selling Price - Cost
Sum of digits is multiple of 3
n! / (n - r)!

16. Circular permutation: The number of ways to arrange n distinct objects along a fixed circle is?
Odd
(n-1)!
Last two digits are multiple of 4 or the number can be divided by 2 twice.
market value

17. (1/4)^2
principle (interest rate - in decimal form) (time - in years)
4/3 TT r ^3
Purchase price
1/16

18. Net
The amount after deductions
Odd numbers only have ___________
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.
| A union B| = |A| + |B| - |A intersect B|

19. Gross Profit formula
Gross Profit = Selling Price - Cost
Principal (1 + interest/number times compounded)^(t)(n)
1.4
principle (interest rate - in decimal form) (time - in years)

20. How to check whether number is multiple of 9
Odd
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 9
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.

21. How to check whether a number is a multiple of 12.
Organize into a grid.
Sum of digits is multiple of 3 - last two digits multiple of 4.
12^3
$11 - 025

22. 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
Group 1 + Group 2 + Neither - Both = Total
| A union B| = |A| + |B| - |A intersect B|
Balancing
1/16

23. Compound interest rule
For a fixed distance - the average speed is inversely related to the amount of time required to make the trip.
Find simple interest then look for the answer that is a little bigger
(# of favorable outcomes) / (# of possible outcomes)
gcd(m,n)*lcm(m,n) = mn

24. Simple Interest Formula (remember this is the total amount of money in the bank after the interest is earned)
Odd
12^3
A = P(1 + r) ^n
For a fixed distance - the average speed is inversely related to the amount of time required to make the trip.

25. 2n+1 - 2n+3 - 2n+5
at least 3 steps
Odd
market value
(# of favorable outcomes) / (# of possible outcomes)

26. Odd and Even rule.
P(E) + P(F) - P(E and F)
n! / (n - r)!
The amount after deductions
Any multiplication involving an even number creates an even product.

27. 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.
Sum of digits is multiple of 3 - last two digits multiple of 4.
Organize into a grid.
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.
Odd

28. The average of consecutive numbers
The average of a set of evenly spaced consecutive numbers is the average of the smallest and largest numbers in the set.
(sum of bases)(height) / 2
P(event NOT occurring) = 1 - P(event occurring)
______ |m-n|

29. How to find the slope.
Divide 4999 by 15 => 333 integers
Principal (1 + interest/number times compounded)^(t)(n)
y2 - y1 / x2 - x1
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.

30. Multiples of 3
If the outcome of one event affects the outcome of the other event.
Find all prime factors
3 - 6 - 9 - 12
Any multiplication involving an even number creates an even product.

31. 1/8 = what %
Last two digits are multiple of 4 or the number can be divided by 2 twice.
| A union B| = |A| + |B| - |A intersect B|
12.5%
The probability of event occurring is...

32. Percent Formula
(sum of bases)(height) / 2
Sum of digits is multiple of 3 - last two digits multiple of 4.
The number of ways independent events can occur together can be determined by multiplying together the number of possible outcomes for each event.
p/100 = is/of

33. Quadratic formula
Total = mean x (number of terms) Number deleted = (original total) - (new total) Number added = (new total) - (original total)
Sum of digits is multiple of 9
Immediately UNFACTOR or vice versa
-b +- sq. rt(b^2 - 4ac) / 2a

34. In general - medium questions require how many steps to solve?
Odd
347
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
2 steps

35. Formula for area of a Trapezoid
Divide 4999 by 15 => 333 integers
y2 - y1 / x2 - x1
-b +- sq. rt(b^2 - 4ac) / 2a
(sum of bases)(height) / 2

36. Prime Factorization to find Greatest Common Factor
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
1st Rule of Probability: Basic Rule is what?
multiply or divide the numbers outside the radical signs - then the numbers inside the radical signs
1/16

37. gcd(m,n)
______ |m-n|
Even integer. Neither positive nor negative. Multiple of every number. Not a factor of any number.
market value
A = P(1 + r) ^n

38. 0! = ?
gcd(m,n)*lcm(m,n) = mn
P(E) + P(F) - P(E and F)
D or E
1

39. Formula for Mixed Group problems (involving Both/Neither)
______ |m-n|
P(E)P(F)
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

40. In general - difficult questions require how many steps to solve?
1 - P(E)
at least 3 steps
2 steps
Group 1 + Group 2 + Neither - Both = Total

41. Work problem rule
347
Find simple interest then look for the answer that is a little bigger
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.
Any multiplication involving an even number creates an even product.

42. How to check for a prime number.

43. The number of ways independent events can occur together.
Principal (1 + interest/number times compounded)^(t)(n)
Divide 4999 by 15 => 333 integers
The number of ways independent events can occur together can be determined by multiplying together the number of possible outcomes for each event.
(total distance) / (total time)

44. Number of integers from A to B inclusive = B - A + 1 - How many consecutive integers are there from 73 through 419 - inclusive?
always try to factor
Balancing
The total amount before any deductions
347

45. Since Mieko's average speed was 3/4 of Chan's - her time was 4/3 as long.
180(n-2)
For a fixed distance - the average speed is inversely related to the amount of time required to make the trip.
Even integer. Neither positive nor negative. Multiple of every number. Not a factor of any number.
3-4-5 - 5-12-13 - 9-12-15

46. Gross
The total amount before any deductions
Gross Profit = Selling Price - Cost
______ |m-n|
(total distance) / (total time)

47. Combined Events: E and F
______ |m-n|
22
P(E)P(F)
Divide 4999 by 15 => 333 integers

48. Permutations: Order Matters
0.15n + 0.08(5) = 0.1(n+5)
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.
Gross Profit = Selling Price - Cost
n! / (n - r)!

49. Simple Interest formula (remember this is only the interest earned - not the total amount of money present in the bank after interest earned)
principle (interest rate - in decimal form) (time - in years)
| A union B| = |A| + |B| - |A intersect B|
(# of favorable outcomes) / (# of possible outcomes)
The total amount before any deductions

50. Three triangle length patterns
Find all prime factors
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
3-4-5 - 5-12-13 - 9-12-15
12^3