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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. Odd and Even rule.
The total amount before any deductions
Purchase price
Any multiplication involving an even number creates an even product.
A = P(1 + r) ^n

2. 2nd Rule of Probability: P(E) = 1 - P(not E)
2 steps
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
D or E

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
Find all prime factors
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.
1.4
4/3 TT r ^3

4. Price purchased for by wholesaler
180(n-2)
14 liters
Sum of digits is multiple of 3
Purchase price

5. x^r/s = ?
Sum of digits is multiple of 3 - last two digits multiple of 4.
s Sq. rt (x^r)
Last two digits are multiple of 4 or the number can be divided by 2 twice.
(# of favorable outcomes) / (# of possible outcomes)

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?
principle (interest rate - in decimal form) (time - in years)
347
14 liters
(n-1)!

7. How do you multiply roots together.
multiply or divide the numbers outside the radical signs - then the numbers inside the radical signs
Odd numbers only have ___________
The number of ways independent events can occur together can be determined by multiplying together the number of possible outcomes for each event.
4/3 TT r ^3

8. gcd(m,n)*lcm(m,n)
gcd(m,n)*lcm(m,n) = mn
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(E)P(F)
D or E

9. gcd(m,n)
______ |m-n|
Total = mean x (number of terms) Number deleted = (original total) - (new total) Number added = (new total) - (original total)
-b +- sq. rt(b^2 - 4ac) / 2a
Find simple interest then look for the answer that is a little bigger

10. Compound interest rule
s Sq. rt (x^r)
always try to factor
Sum of digits is multiple of 3 - last two digits multiple of 4.
Find simple interest then look for the answer that is a little bigger

11. 1/8 = what %
12.5%
Sum of digits is multiple of 3 - last two digits multiple of 4.
(x-n(n)y-n)
2 steps

12. When you see an equation in factored form in a question?
(sum of bases)(height) / 2
(amount of change) / (original amount)
The number of ways independent events can occur together can be determined by multiplying together the number of possible outcomes for each event.
Immediately UNFACTOR or vice versa

13. Probability and Geometry.
The number of ways independent events can occur together can be determined by multiplying together the number of possible outcomes for each event.
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
Figure out the probability for each individual event. Multiply the individual probabilities together.
1st Rule of Probability: Basic Rule is what?

14. 5/6 = what %
4/3 TT r ^3
22
The probability of event occurring is...
83.3%

15. Gross
The total amount before any deductions
Even
P(E)P(F)
(# of favorable outcomes) / (# of possible outcomes)

16. How to find all divisors of a number
market value
Immediately try factoring/simplifying when possible
Find all prime factors
Total = mean x (number of terms) Number deleted = (original total) - (new total) Number added = (new total) - (original total)

17. Trial Problems: look at the probability of NOT OCCURRING
16.6%
The probability of event occurring is...
P(event NOT occurring) = 1 - P(event occurring)
at least 3 steps

18. In general - medium questions require how many steps to solve?
(total distance) / (total time)
2 steps
______ |m-n|
Even integer. Neither positive nor negative. Multiple of every number. Not a factor of any number.

19. Simple Interest Formula (remember this is the total amount of money in the bank after the interest is earned)
1.7
A = P(1 + r) ^n
always try to factor
s Sq. rt (x^r)

20. Multiplication principle
16.6%
market value
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 average of a set of evenly spaced consecutive numbers is the average of the smallest and largest numbers in the set.

21. To determine the number of integers less than 5000 that are evenly divisible by 15...?
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.
gcd(m,n)*lcm(m,n) = mn
Find simple interest then look for the answer that is a little bigger

22. The number of ways independent events can occur together.
83.3%
Balancing
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 number of ways independent events can occur together can be determined by multiplying together the number of possible outcomes for each event.

23. If you have to guess in a problem - which ones should you guess? Especially if you have to plug numbers.
D or E
P(E)P(F)
gcd(m,n)*lcm(m,n) = mn
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

24. Gross Profit formula
180(n-2)
Find simple interest then look for the answer that is a little bigger
P(E)P(F)
Gross Profit = Selling Price - Cost

25. Combined Events: Not E = P(not E) = ?
1 - P(E)
1
Total = mean x (number of terms) Number deleted = (original total) - (new total) Number added = (new total) - (original total)
347

26. Set Problems formula
Sum of digits is multiple of 3
(x-n(n)y-n)
always try to factor
If the outcome of one event affects the outcome of the other event.

27. What does the Sum of the angles in a Regular Polygon formula look like?
180(n-2)
Sum of digits is multiple of 9
Sum of digits is multiple of 3
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.

28. Prime Factorization to find Greatest Common Factor
(x-n(n)y-n)
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
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

29. Simple probability
The probability of event occurring is...
(# of favorable outcomes) / (# of possible outcomes)
Total = mean x (number of terms) Number deleted = (original total) - (new total) Number added = (new total) - (original total)
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.

30. Intersecting Sets
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.
| A union B| = |A| + |B| - |A intersect B|
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.

31. Three triangle length patterns
1/16
(total distance) / (total time)
3-4-5 - 5-12-13 - 9-12-15
Sum of digits is multiple of 3 - last two digits multiple of 4.

32. How to check whether number is multiple of 9
Sum of digits is multiple of 9
Odd numbers only have ___________
Gross Profit = Selling Price - Cost
12.5%

33. Formula for Mixed Group problems (involving Both/Neither)
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)
347
Group 1 + Group 2 + Neither - Both = Total
4/3 TT r ^3

34. The number of outcomes that result in A divided by the total number of possible outcomes.
Immediately UNFACTOR or vice versa
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.
Divide 4999 by 15 => 333 integers
The probability of event occurring is...

35. Properties of 0
16.6%
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
Even integer. Neither positive nor negative. Multiple of every number. Not a factor of any number.
P(event NOT occurring) = 1 - P(event occurring)

36. Compound interest formula
1/16
Principal (1 + interest/number times compounded)^(t)(n)
Even integer. Neither positive nor negative. Multiple of every number. Not a factor of any number.
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

37. Always try to factor
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)
s Sq. rt (x^r)
For a fixed distance - the average speed is inversely related to the amount of time required to make the trip.
always try to factor

38. 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?
Group 1 + Group 2 + Neither - Both = Total
0.15n + 0.08(5) = 0.1(n+5)
180(n-2)
The number of ways independent events can occur together can be determined by multiplying together the number of possible outcomes for each event.

39. If $10 -000 is invested at 10% annual interest - compounded semi-annually - what is the balance after 1 year?
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.
multiply or divide the numbers outside the radical signs - then the numbers inside the radical signs
sum = (average)(number of terms)
$11 - 025

40. 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.
83.3%
12^3
Immediately try factoring/simplifying when possible
1st Rule of Probability: Basic Rule is what?

41. Indistinguishable events how to find the number of permutations

42. 4th rule of Probability
1st Rule of Probability: Basic Rule is what?
Immediately UNFACTOR or vice versa
P(E)P(F)
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)

43. The average of 5 numbers is 2. After one number is deleted - the new average is -3. What number was deleted?
22
x - x - x(sq. rt 2)
y2 - y1 / x2 - x1
Organize into a grid.

44. How to find the slope.
(amount of change) / (original amount)
83.3%
The probability of an event occurring plus the probability of the event not occurring = 1
y2 - y1 / x2 - x1

45. Combined Events: E and F
multiply or divide the numbers outside the radical signs - then the numbers inside the radical signs
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
P(E)P(F)

46. Quadratic formula
-b +- sq. rt(b^2 - 4ac) / 2a
The probability of event occurring is...
(total distance) / (total time)
The amount after deductions

47. Average Rate: Average speed
______ |m-n|
(total distance) / (total time)
Organize into a grid.
s Sq. rt (x^r)

48. Odd Factors
Even
The probability of an event occurring plus the probability of the event not occurring = 1
Odd numbers only have ___________
-b +- sq. rt(b^2 - 4ac) / 2a

49. How to check whether a number is a multiple of 4.
Last two digits are multiple of 4 or the number can be divided by 2 twice.
(total A) / (total B)
(amount of change) / (original amount)
Number is a multiple of 3 and 2

50. Inscribed Angle - Minor Arc
(total distance) / (total time)
Even integer. Neither positive nor negative. Multiple of every number. Not a factor of any number.
Minor arc = 2(inscribed angle)
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.