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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. Dependent events: When are two events said to be dependent events?
If the outcome of one event affects the outcome of the other event.
P(E) + P(F) - P(E and F)
The amount after deductions
Any multiplication involving an even number creates an even product.

2. The number of outcomes that result in A divided by the total number of possible outcomes.
The probability of event occurring is...
1.4
principle (interest rate - in decimal form) (time - in years)
Number is a multiple of 3 and 2

3. How to check whether a number is a multiple of 3.
Sum of digits is multiple of 3
Any multiplication involving an even number creates an even product.
(total distance) / (total time)
Total = mean x (number of terms) Number deleted = (original total) - (new total) Number added = (new total) - (original total)

4. Sum of consecutive numbers
sum = (average)(number of terms)
x(sq. rt 3) - x - 2x
Odd numbers only have ___________
Odd

5. How to find the slope.
1.7
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.
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
y2 - y1 / x2 - x1

6. How many liters of a solution that is 10% alcohol by volume must be added to 2 liters of a solution that is 50% alcohol by volume to create a solution that is 15% alcohol by volume?
Sum of digits is multiple of 3 - last two digits multiple of 4.
Total = mean x (number of terms) Number deleted = (original total) - (new total) Number added = (new total) - (original total)
Group 1 + Group 2 + Neither - Both = Total
14 liters

7. 3rd Rule of Probability: Conditional Probability
1.7
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 = (average)(number of terms)
Sum of digits is multiple of 3

8. To determine multiple-event probability where each individual event must occur in a certain way.
Figure out the probability for each individual event. Multiply the individual probabilities together.
Principal (1 + interest/number times compounded)^(t)(n)
Odd
3-4-5 - 5-12-13 - 9-12-15

9. How to check whether a number is a multiple of 12.
The probability of an event occurring plus the probability of the event not occurring = 1
s Sq. rt (x^r)
Balancing
Sum of digits is multiple of 3 - last two digits multiple of 4.

10. If you have to guess in a problem - which ones should you guess? Especially if you have to plug numbers.
Last two digits are multiple of 4 or the number can be divided by 2 twice.
14 liters
D or E
1.7

11. Number of integers from A to B inclusive = B - A + 1 - How many consecutive integers are there from 73 through 419 - inclusive?
347
1.4
2 steps
-b +- sq. rt(b^2 - 4ac) / 2a

12. Combined Events: E or F
x(sq. rt 3) - x - 2x
12.5%
$11 - 025
P(E) + P(F) - P(E and F)

13. 1. A and B < A or B 2. A or B > Individual probabilities of A - B 3. P(A and B) = P(A) x P(B) <-- 'fewer options' 4. P(A or B) = P(A) + P(B) <-- 'more options' - Probability of multiple events rules.
Total = mean x (number of terms) Number deleted = (original total) - (new total) Number added = (new total) - (original total)
1st Rule of Probability: Basic Rule is what?
Find all prime factors
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.

14. Number added or deleted
Gross Profit = Selling Price - Cost
Total = mean x (number of terms) Number deleted = (original total) - (new total) Number added = (new total) - (original total)
The total amount before any deductions
Sum of digits is multiple of 3

15. Inscribed Angle - Minor Arc
(n-1)!
1.7
If the outcome of one event affects the outcome of the other event.
Minor arc = 2(inscribed angle)

16. Odd and Even rule.
(sum of bases)(height) / 2
Any multiplication involving an even number creates an even product.
Last two digits are multiple of 4 or the number can be divided by 2 twice.
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.

17. Simple Interest formula (remember this is only the interest earned - not the total amount of money present in the bank after interest earned)
Divide 4999 by 15 => 333 integers
P(E) + P(F) - P(E and F)
principle (interest rate - in decimal form) (time - in years)
(n-1)!

18. Net
(x-n(n)y-n)
Sum of digits is multiple of 9
-b +- sq. rt(b^2 - 4ac) / 2a
The amount after deductions

19. What does the Sum of the angles in a Regular Polygon formula look like?
Minor arc = 2(inscribed angle)
Principal (1 + interest/number times compounded)^(t)(n)
180(n-2)
Figure out the probability for each individual event. Multiply the individual probabilities together.

20. 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
The amount after deductions
Purchase price
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. 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

21. Compound interest formula
Last two digits are multiple of 4 or the number can be divided by 2 twice.
Principal (1 + interest/number times compounded)^(t)(n)
x(sq. rt 3) - x - 2x
2 steps

22. 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.
If the outcome of one event affects the outcome of the other event.
Number is a multiple of 3 and 2
12.5%

23. Odd Factors
P(E) + P(F) - P(E and F)
1/16
gcd(m,n)*lcm(m,n) = mn
Odd numbers only have ___________

24. Percent Formula
p/100 = is/of
market value
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

25. Combined Events: Not E = P(not E) = ?
(total distance) / (total time)
If the outcome of one event affects the outcome of the other event.
1 - P(E)
The total amount before any deductions

26. 1/6 = what %
1/16
16.6%
Immediately UNFACTOR or vice versa
Minor arc = 2(inscribed angle)

27. 30-60-90 triangle basic lengths of sides
(total distance) / (total time)
x(sq. rt 3) - x - 2x
12.5%
Immediately try factoring/simplifying when possible

28. When you see an equation in factored form in a question?
n! / (n - r)!
Immediately UNFACTOR or vice versa
1 - P(E)
The number of ways independent events can occur together can be determined by multiplying together the number of possible outcomes for each event.

29. Formula for area of a Trapezoid
(sum of bases)(height) / 2
s Sq. rt (x^r)
Figure out the probability for each individual event. Multiply the individual probabilities together.
Organize into a grid.

30. Compound interest rule
A = P(1 + r) ^n
Find simple interest then look for the answer that is a little bigger
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)
1

31. Probability and Geometry.
market value
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
1.4
Gross Profit = Selling Price - Cost

32. 2n - 2n+2 - 2n+4
Even
sum = (average)(number of terms)
Figure out the probability for each individual event. Multiply the individual probabilities together.
(x-n(n)y-n)

33. gcd(m,n)
1.7
______ |m-n|
n! / (n - r)!
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.

34. 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
12.5%
Immediately try factoring/simplifying when possible
12^3
Balancing

35. 45-45-90 triangle basic lengths of sides
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.
x - x - x(sq. rt 2)
1/16
Organize into a grid.

36. Quadratic formula
-b +- sq. rt(b^2 - 4ac) / 2a
at least 3 steps
Even
Immediately try factoring/simplifying when possible

37. 5/6 = what %
1st Rule of Probability: Basic Rule is what?
83.3%
Group 1 + Group 2 + Neither - Both = Total
n! / (n - r)!

38. In general - difficult questions require how many steps to solve?
gcd(m,n)*lcm(m,n) = mn
1.4
at least 3 steps
Total = mean x (number of terms) Number deleted = (original total) - (new total) Number added = (new total) - (original total)

39. How to check whether number is multiple of 9
Sum of digits is multiple of 9
P(E)P(F)
x - x - x(sq. rt 2)
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

40. 2n+1 - 2n+3 - 2n+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.
D or E
Find all prime factors
Odd

41. The number of ways independent events can occur together.
Immediately UNFACTOR or vice versa
The number of ways independent events can occur together can be determined by multiplying together the number of possible outcomes for each event.
Odd
P(E)P(F)

42. 3^3 x 4^3 = ?
gcd(m,n)*lcm(m,n) = mn
(amount of change) / (original amount)
market value
12^3

43. Price purchased for by wholesaler
Purchase price
P(event NOT occurring) = 1 - P(event occurring)
1.7
Even

44. Three triangle length patterns
The number of ways independent events can occur together can be determined by multiplying together the number of possible outcomes for each event.
3-4-5 - 5-12-13 - 9-12-15
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.
Odd

45. Simple probability
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)
Balancing
(# of favorable outcomes) / (# of possible outcomes)
1.4

46. Gross
market value
The total amount before any deductions
0.15n + 0.08(5) = 0.1(n+5)
Immediately UNFACTOR or vice versa

47. (1/4)^2
180(n-2)
1/16
1 - P(E)
Last two digits are multiple of 4 or the number can be divided by 2 twice.

48. Sq. rt(3)
1.7
0.15n + 0.08(5) = 0.1(n+5)
P(event NOT occurring) = 1 - P(event occurring)
1/16

49. Permutations: Order Matters
n! / (n - r)!
If the outcome of one event affects the outcome of the other event.
P(event NOT occurring) = 1 - P(event occurring)
2 steps

50. How to find all divisors of a number
P(E)P(F)
n! / (n - r)!
14 liters
Find all prime factors