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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. Set Problems formula
1.7
(x-n(n)y-n)
If the outcome of one event affects the outcome of the other event.
Sum of digits is multiple of 3 - last two digits multiple of 4.

2. Quadratic formula
(sum of bases)(height) / 2
Organize into a grid.
-b +- sq. rt(b^2 - 4ac) / 2a
22

3. Number of integers from A to B inclusive = B - A + 1 - How many consecutive integers are there from 73 through 419 - inclusive?
347
Find all prime factors
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
The amount after deductions

4. Permutations: Order Matters
14 liters
n! / (n - r)!
(n-1)!
market value

5. What to do with equations that have fractions
(amount of change) / (original amount)
3 - 6 - 9 - 12
multiply or divide the numbers outside the radical signs - then the numbers inside the radical signs
Immediately try factoring/simplifying when possible

6. Combined Events: E and F
Organize into a grid.
P(E)P(F)
1/16
principle (interest rate - in decimal form) (time - in years)

7. Price sold for by retailer (after markup)
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
$11 - 025
market value

8. If you have to guess in a problem - which ones should you guess? Especially if you have to plug numbers.
D or E
| A union B| = |A| + |B| - |A intersect B|
at least 3 steps
Odd

9. How to check whether number is multiple of 9
Organize into a grid.
Sum of digits is multiple of 9
P(E) + P(F) - P(E and F)
Even integer. Neither positive nor negative. Multiple of every number. Not a factor of any number.

10. Work problem rule
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. 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?
| A union B| = |A| + |B| - |A intersect B|

11. Prime Factorization to find Greatest Common Factor
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.
______ |m-n|
22
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

12. The number of ways independent events can occur together.
The number of ways independent events can occur together can be determined by multiplying together the number of possible outcomes for each event.
3 - 6 - 9 - 12
sum = (average)(number of terms)
1/16

13. Odd and Even rule.
If the outcome of one event affects the outcome of the other event.
180(n-2)
2 steps
Any multiplication involving an even number creates an even product.

14. gcd(m,n)
Organize into a grid.
Odd numbers only have ___________
x - x - x(sq. rt 2)
______ |m-n|

15. Simple probability
s Sq. rt (x^r)
(# of favorable outcomes) / (# of possible outcomes)
If the outcome of one event affects the outcome of the other event.
(total A) / (total B)

16. The number of outcomes that result in A divided by the total number of possible outcomes.
P(event NOT occurring) = 1 - P(event occurring)
12^3
The probability of event occurring is...
12.5%

17. Since Mieko's average speed was 3/4 of Chan's - her time was 4/3 as long.
14 liters
The total amount before any deductions
For a fixed distance - the average speed is inversely related to the amount of time required to make the trip.
Gross Profit = Selling Price - Cost

18. What does the Sum of the angles in a Regular Polygon formula look like?
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.
Exterior angle d is equal to the sum of the two remote interior angles a and b
180(n-2)
Odd numbers only have ___________

19. In general - difficult questions require how many steps to solve?
D or E
Group 1 + Group 2 + Neither - Both = Total
at least 3 steps
$11 - 025

20. Percent Formula
Immediately UNFACTOR or vice versa
p/100 = is/of
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 probability of an event occurring plus the probability of the event not occurring = 1

21. Simple Interest Formula (remember this is the total amount of money in the bank after the interest is earned)
y2 - y1 / x2 - x1
Minor arc = 2(inscribed angle)
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
A = P(1 + r) ^n

22. Trial Problems: look at the probability of NOT OCCURRING
For a fixed distance - the average speed is inversely related to the amount of time required to make the trip.
83.3%
P(event NOT occurring) = 1 - P(event occurring)
(total distance) / (total time)

23. How to check whether a number is a multiple of 6
Balancing
at least 3 steps
1.7
Number is a multiple of 3 and 2

24. How to check whether a number is a multiple of 4.
Organize into a grid.
x(sq. rt 3) - x - 2x
83.3%
Last two digits are multiple of 4 or the number can be divided by 2 twice.

25. Multiples of 3
3 - 6 - 9 - 12
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.
at least 3 steps
22

26. 4th rule of Probability
The probability of an event occurring plus the probability of the event not occurring = 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)
4/3 TT r ^3
12^3

27. Probability and Geometry.
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
multiply or divide the numbers outside the radical signs - then the numbers inside the radical signs
at least 3 steps
1 - P(E)

28. 1/6 = what %
x(sq. rt 3) - x - 2x
16.6%
For a fixed distance - the average speed is inversely related to the amount of time required to make the trip.
12.5%

29. 2n+1 - 2n+3 - 2n+5
Odd
1 - P(E)
multiply or divide the numbers outside the radical signs - then the numbers inside the radical signs
12^3

30. 45-45-90 triangle basic lengths of sides
D or E
Last two digits are multiple of 4 or the number can be divided by 2 twice.
x - x - x(sq. rt 2)
Total = mean x (number of terms) Number deleted = (original total) - (new total) Number added = (new total) - (original total)

31. Sum of consecutive numbers
Purchase price
always try to factor
sum = (average)(number of terms)
The number of ways independent events can occur together can be determined by multiplying together the number of possible outcomes for each event.

32. Odd Factors
$11 - 025
Odd numbers only have ___________
3 - 6 - 9 - 12
gcd(m,n)*lcm(m,n) = mn

33. 3^3 x 4^3 = ?
12^3
The total amount before any deductions
1/16
Odd numbers only have ___________

34. Combined Events: Not E = P(not E) = ?
1 - P(E)
1.4
Number is a multiple of 3 and 2
347

35. The average of 5 numbers is 2. After one number is deleted - the new average is -3. What number was deleted?
22
Odd numbers only have ___________
x(sq. rt 3) - x - 2x
12^3

36. 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.
$11 - 025
1/16
A = P(1 + r) ^n

37. Formula for area of a Trapezoid
180(n-2)
(total distance) / (total time)
Sum of digits is multiple of 3 - last two digits multiple of 4.
(sum of bases)(height) / 2

38. To determine the number of integers less than 5000 that are evenly divisible by 15...?
principle (interest rate - in decimal form) (time - in years)
The probability of event occurring is...
Immediately UNFACTOR or vice versa
Divide 4999 by 15 => 333 integers

39. 0! = ?
(amount of change) / (original amount)
Exterior angle d is equal to the sum of the two remote interior angles a and b
1
(n-1)!

40. Volume of a sphere
4/3 TT r ^3
The number of ways independent events can occur together can be determined by multiplying together the number of possible outcomes for each event.
$11 - 025
P(event NOT occurring) = 1 - P(event occurring)

41. Gross Profit formula
The amount after deductions
Divide 4999 by 15 => 333 integers
Immediately try factoring/simplifying when possible
Gross Profit = Selling Price - Cost

42. 2n - 2n+2 - 2n+4
347
Even
Find simple interest then look for the answer that is a little bigger
x(sq. rt 3) - x - 2x

43. Price purchased for by wholesaler
Balancing
For a fixed distance - the average speed is inversely related to the amount of time required to make the trip.
Purchase price
1st Rule of Probability: Basic Rule is what?

44. gcd(m,n)*lcm(m,n)
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.
gcd(m,n)*lcm(m,n) = mn
multiply or divide the numbers outside the radical signs - then the numbers inside the radical signs
Number is a multiple of 3 and 2

45. Percent increase = ?
(amount of change) / (original amount)
$11 - 025
4/3 TT r ^3
Immediately try factoring/simplifying when possible

46. Multiplication principle
s Sq. rt (x^r)
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.
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

47. Formula for Mixed Group problems (involving Both/Neither)
(sum of bases)(height) / 2
Group 1 + Group 2 + Neither - Both = Total
The probability of event occurring is...
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.

48. When you see an equation in factored form in a question?
1/16
s Sq. rt (x^r)
Immediately UNFACTOR or vice versa
Principal (1 + interest/number times compounded)^(t)(n)

49. x^r/s = ?
P(E)P(F)
s Sq. rt (x^r)
(n-1)!
0.15n + 0.08(5) = 0.1(n+5)

50. Properties of 0
3 - 6 - 9 - 12
Even integer. Neither positive nor negative. Multiple of every number. Not a factor of any number.
22
Last two digits are multiple of 4 or the number can be divided by 2 twice.