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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. Simple Interest formula (remember this is only the interest earned - not the total amount of money present in the bank after interest earned)
12.5%
Total = mean x (number of terms) Number deleted = (original total) - (new total) Number added = (new total) - (original total)
s Sq. rt (x^r)
principle (interest rate - in decimal form) (time - in years)

2. 2n+1 - 2n+3 - 2n+5
Odd
P(E) + P(F) - P(E and F)
Find all prime factors
(amount of change) / (original amount)

3. 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.
Immediately UNFACTOR or vice versa
Organize into a grid.
180(n-2)
Last two digits are multiple of 4 or the number can be divided by 2 twice.

4. 30-60-90 triangle basic lengths of sides
P(E)P(F)
market value
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(sq. rt 3) - x - 2x

5. Compound interest formula
Sum of digits is multiple of 9
p/100 = is/of
Find all prime factors
Principal (1 + interest/number times compounded)^(t)(n)

6. Gross Profit formula
83.3%
Divide 4999 by 15 => 333 integers
Gross Profit = Selling Price - Cost
sum = (average)(number of terms)

7. What does the Sum of the angles in a Regular Polygon formula look like?
Even integer. Neither positive nor negative. Multiple of every number. Not a factor of any number.
16.6%
180(n-2)
Any multiplication involving an even number creates an even product.

8. The average of consecutive numbers
(amount of change) / (original amount)
Figure out the probability for each individual event. Multiply the individual probabilities together.
The average of a set of evenly spaced consecutive numbers is the average of the smallest and largest numbers in the set.
P(E) + P(F) - P(E and F)

9. Sq. rt(3)
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.
| A union B| = |A| + |B| - |A intersect B|
1.7
For a fixed distance - the average speed is inversely related to the amount of time required to make the trip.

10. Formula for area of a Trapezoid
Find all prime factors
Divide 4999 by 15 => 333 integers
(sum of bases)(height) / 2
A = P(1 + r) ^n

11. Combined Events: E and F
P(E)P(F)
y2 - y1 / x2 - x1
1 - P(E)
Last two digits are multiple of 4 or the number can be divided by 2 twice.

12. Prime Factorization to find Greatest Common Factor
(# of favorable outcomes) / (# of possible outcomes)
Purchase price
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
market value

13. Number added or deleted
principle (interest rate - in decimal form) (time - in years)
12^3
Principal (1 + interest/number times compounded)^(t)(n)
Total = mean x (number of terms) Number deleted = (original total) - (new total) Number added = (new total) - (original total)

14. Intersecting Sets
Sum of digits is multiple of 3 - last two digits multiple of 4.
83.3%
12.5%
| A union B| = |A| + |B| - |A intersect B|

15. 2n - 2n+2 - 2n+4
Even
(total distance) / (total time)
2 steps
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.

16. 4th rule of Probability
16.6%
Figure out the probability for each individual event. Multiply the individual probabilities together.
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)
(total distance) / (total time)

17. Multiplication principle
Group 1 + Group 2 + Neither - Both = Total
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
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)
Divide 4999 by 15 => 333 integers

18. How to check whether a number is a multiple of 6
x(sq. rt 3) - x - 2x
n! / (n - r)!
Number is a multiple of 3 and 2
22

19. How many liters of a solution that is 15% salt must be added to 5 liters of a solution that is 8% salt so that the resulting mixture is 10% salt?
0.15n + 0.08(5) = 0.1(n+5)
For a fixed distance - the average speed is inversely related to the amount of time required to make the trip.
180(n-2)
12.5%

20. 2nd Rule of Probability: P(E) = 1 - P(not E)
n! / (n - r)!
The probability of an event occurring plus the probability of the event not occurring = 1
2 steps
x(sq. rt 3) - x - 2x

21. gcd(m,n)
(# of favorable outcomes) / (# of possible outcomes)
______ |m-n|
0.15n + 0.08(5) = 0.1(n+5)
Last two digits are multiple of 4 or the number can be divided by 2 twice.

22. Odd and Even rule.
16.6%
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.
Any multiplication involving an even number creates an even product.
Divide 4999 by 15 => 333 integers

23. Quadratic formula
-b +- sq. rt(b^2 - 4ac) / 2a
Group 1 + Group 2 + Neither - Both = Total
(sum of bases)(height) / 2
Divide 4999 by 15 => 333 integers

24. Permutations: Order Matters
(total A) / (total B)
12.5%
n! / (n - r)!
The probability of an event occurring plus the probability of the event not occurring = 1

25. Set Problems formula
| A union B| = |A| + |B| - |A intersect B|
P(E)P(F)
Even
(x-n(n)y-n)

26. When you see an equation in factored form in a question?
Odd numbers only have ___________
Immediately try factoring/simplifying when possible
Immediately UNFACTOR or vice versa
Sum of digits is multiple of 3 - last two digits multiple of 4.

27. Volume of a sphere
Figure out the probability for each individual event. Multiply the individual probabilities together.
market value
4/3 TT r ^3
Any multiplication involving an even number creates an even product.

28. In general - difficult questions require how many steps to solve?
83.3%
P(E)P(F)
Gross Profit = Selling Price - Cost
at least 3 steps

29. Average Rate: Average A per B
x(sq. rt 3) - x - 2x
(total A) / (total B)
-b +- sq. rt(b^2 - 4ac) / 2a
If the outcome of one event affects the outcome of the other event.

30. Triangle abc with d on the outside with a line. What does d = ?
3-4-5 - 5-12-13 - 9-12-15
Principal (1 + interest/number times compounded)^(t)(n)
Exterior angle d is equal to the sum of the two remote interior angles a and b
Find all prime factors

31. Work problem rule
Immediately try factoring/simplifying when possible
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
p/100 = is/of

32. How to check whether a number is a multiple of 12.
Sum of digits is multiple of 9
Sum of digits is multiple of 3 - last two digits multiple of 4.
Immediately UNFACTOR or vice versa
14 liters

33. The number of outcomes that result in A divided by the total number of possible outcomes.
Odd
The probability of event occurring is...
Principal (1 + interest/number times compounded)^(t)(n)
The average of a set of evenly spaced consecutive numbers is the average of the smallest and largest numbers in the set.

34. Multiples of 3
multiply or divide the numbers outside the radical signs - then the numbers inside the radical signs
Find simple interest then look for the answer that is a little bigger
3 - 6 - 9 - 12
2 steps

35. Simple probability
(sum of bases)(height) / 2
Immediately UNFACTOR or vice versa
16.6%
(# of favorable outcomes) / (# of possible outcomes)

36. Number of integers from A to B inclusive = B - A + 1 - How many consecutive integers are there from 73 through 419 - inclusive?
Even
347
The probability of an event occurring plus the probability of the event not occurring = 1
Immediately UNFACTOR or vice versa

37. Properties of 0
| A union B| = |A| + |B| - |A intersect B|
x - x - x(sq. rt 2)
multiply or divide the numbers outside the radical signs - then the numbers inside the radical signs
Even integer. Neither positive nor negative. Multiple of every number. Not a factor of any number.

38. Gross
The total amount before any deductions
(total A) / (total B)
(# of favorable outcomes) / (# of possible outcomes)
n! / (n - r)!

39. 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.
1st Rule of Probability: Basic Rule is what?
D or E
3-4-5 - 5-12-13 - 9-12-15
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

40. Compound interest rule
0.15n + 0.08(5) = 0.1(n+5)
Minor arc = 2(inscribed angle)
Group 1 + Group 2 + Neither - Both = Total
Find simple interest then look for the answer that is a little bigger

41. 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?
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
14 liters
22
P(E) + P(F) - P(E and F)

42. 3^3 x 4^3 = ?
sum = (average)(number of terms)
s Sq. rt (x^r)
12^3
347

43. To determine the number of integers less than 5000 that are evenly divisible by 15...?
Divide 4999 by 15 => 333 integers
The total amount before any deductions
Figure out the probability for each individual event. Multiply the individual probabilities together.
The probability of an event occurring plus the probability of the event not occurring = 1

44. Sq. rt(2)
1.4
2 steps
$11 - 025
Find all prime factors

45. 1/8 = what %
(total A) / (total B)
12.5%
Divide 4999 by 15 => 333 integers
12^3

46. Price sold for by retailer (after markup)
The total amount before any deductions
Balancing
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.
market value

47. Combined Events: E or F
P(E) + P(F) - P(E and F)
1
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.
1st Rule of Probability: Basic Rule is what?

48. Price purchased for by wholesaler
For a fixed distance - the average speed is inversely related to the amount of time required to make the trip.
Find all prime factors
Purchase price
multiply or divide the numbers outside the radical signs - then the numbers inside the radical signs

49. Net
The amount after deductions
The probability of an event occurring plus the probability of the event not occurring = 1
Gross Profit = Selling Price - Cost
Odd numbers only have ___________

50. Trial Problems: look at the probability of NOT OCCURRING
multiply or divide the numbers outside the radical signs - then the numbers inside the radical signs
The total amount before any deductions
P(event NOT occurring) = 1 - P(event occurring)
16.6%