Test your basic knowledge |

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. The number of ways independent events can occur together.
-b +- sq. rt(b^2 - 4ac) / 2a
The number of ways independent events can occur together can be determined by multiplying together the number of possible outcomes for each event.
The probability of an event occurring plus the probability of the event not occurring = 1
(total A) / (total B)

2. Three triangle length patterns
3-4-5 - 5-12-13 - 9-12-15
p/100 = is/of
sum = (average)(number of terms)
The average of a set of evenly spaced consecutive numbers is the average of the smallest and largest numbers in the set.

3. Multiples of 3
market value
Purchase price
3 - 6 - 9 - 12
| A union B| = |A| + |B| - |A intersect B|

4. Simple Interest Formula (remember this is the total amount of money in the bank after the interest is earned)
Number is a multiple of 3 and 2
Even
Organize into a grid.
A = P(1 + r) ^n

5. Percent Formula
p/100 = is/of
2 steps
Figure out the probability for each individual event. Multiply the individual probabilities together.
1.4

6. In general - difficult questions require how many steps to solve?
at least 3 steps
12^3
1 - P(E)
3-4-5 - 5-12-13 - 9-12-15

7. Prime Factorization to find Greatest Common Factor
multiply or divide the numbers outside the radical signs - then the numbers inside the radical signs
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
16.6%

8. 1/8 = what %
Organize into a grid.
$11 - 025
Number is a multiple of 3 and 2
12.5%

9. Price sold for by retailer (after markup)
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
1.7
market value
Last two digits are multiple of 4 or the number can be divided by 2 twice.

10. Simple probability
market value
Any multiplication involving an even number creates an even product.
83.3%
(# of favorable outcomes) / (# of possible outcomes)

11. Indistinguishable events how to find the number of permutations

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

12. 3rd Rule of Probability: Conditional Probability
Gross Profit = Selling Price - Cost
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.
83.3%

13. Sum of consecutive numbers
sum = (average)(number of terms)
14 liters
at least 3 steps
The probability of event occurring is...

14. Number added or deleted
Total = mean x (number of terms) Number deleted = (original total) - (new total) Number added = (new total) - (original total)
| A union B| = |A| + |B| - |A intersect B|
______ |m-n|
12^3

15. 3^3 x 4^3 = ?
12^3
If the outcome of one event affects the outcome of the other event.
n! / (n - r)!
1/16

16. gcd(m,n)*lcm(m,n)
Even
Odd
gcd(m,n)*lcm(m,n) = mn
12.5%

17. Properties of 0
4/3 TT r ^3
347
Even integer. Neither positive nor negative. Multiple of every number. Not a factor of any number.
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.

18. To determine multiple-event probability where each individual event must occur in a certain way.
The average of a set of evenly spaced consecutive numbers is the average of the smallest and largest numbers in the set.
3 - 6 - 9 - 12
1 - P(E)
Figure out the probability for each individual event. Multiply the individual probabilities together.

19. What does the Sum of the angles in a Regular Polygon formula look like?
180(n-2)
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.
(total distance) / (total time)
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.

20. When you see an equation in factored form in a question?
Even
Immediately UNFACTOR or vice versa
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 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)

21. Percent increase = ?
1/16
14 liters
(amount of change) / (original amount)
$11 - 025

22. 1/6 = what %
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.
16.6%
Minor arc = 2(inscribed angle)
y2 - y1 / x2 - x1

23. Quadratic formula
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.
Immediately try factoring/simplifying when possible
347
-b +- sq. rt(b^2 - 4ac) / 2a

24. Formula for Mixed Group problems (involving Both/Neither)
Immediately UNFACTOR or vice versa
Group 1 + Group 2 + Neither - Both = Total
Last two digits are multiple of 4 or the number can be divided by 2 twice.
Gross Profit = Selling Price - Cost

25. 45-45-90 triangle basic lengths of sides
x - x - x(sq. rt 2)
multiply or divide the numbers outside the radical signs - then the numbers inside the radical signs
Last two digits are multiple of 4 or the number can be divided by 2 twice.
14 liters

26. Gross
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
The total amount before any deductions
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.

27. Since Mieko's average speed was 3/4 of Chan's - her time was 4/3 as long.
For a fixed distance - the average speed is inversely related to the amount of time required to make the trip.
Find all prime factors
2 steps
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.

28. 30-60-90 triangle basic lengths of sides
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.
x - x - x(sq. rt 2)
x(sq. rt 3) - x - 2x
Immediately UNFACTOR or vice versa

29. 2nd Rule of Probability: P(E) = 1 - P(not E)
| A union B| = |A| + |B| - |A intersect B|
The probability of an event occurring plus the probability of the event not occurring = 1
14 liters
(# of favorable outcomes) / (# of possible outcomes)

30. Combined Events: Not E = P(not E) = ?
(total distance) / (total time)
0.15n + 0.08(5) = 0.1(n+5)
1 - P(E)
(total A) / (total B)

31. How to check for a prime number.

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

32. 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.
Any multiplication involving an even number creates an even product.
1st Rule of Probability: Basic Rule is what?
P(E)P(F)
market value

33. 4th rule of Probability
2 steps
principle (interest rate - in decimal form) (time - in years)
Exterior angle d is equal to the sum of the two remote interior angles a and b
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)

34. Triangle abc with d on the outside with a line. What does d = ?
Principal (1 + interest/number times compounded)^(t)(n)
4/3 TT r ^3
Exterior angle d is equal to the sum of the two remote interior angles a and b
gcd(m,n)*lcm(m,n) = mn

35. 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.
Principal (1 + interest/number times compounded)^(t)(n)
Number is a multiple of 3 and 2
Organize into a grid.
always try to factor

36. If you have to guess in a problem - which ones should you guess? Especially if you have to plug numbers.
Odd
D or E
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.
4/3 TT r ^3

37. Circular permutation: The number of ways to arrange n distinct objects along a fixed circle is?
P(E)P(F)
(n-1)!
Find simple interest then look for the answer that is a little bigger
4/3 TT r ^3

38. Number of integers from A to B inclusive = B - A + 1 - How many consecutive integers are there from 73 through 419 - inclusive?
Sum of digits is multiple of 9
347
12.5%
Principal (1 + interest/number times compounded)^(t)(n)

39. Probability and Geometry.
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
x - x - x(sq. rt 2)
Sum of digits is multiple of 3

40. 0! = ?
1
Immediately UNFACTOR or vice versa
x - x - x(sq. rt 2)
gcd(m,n)*lcm(m,n) = mn

41. In general - medium questions require how many steps to solve?
2 steps
1st Rule of Probability: Basic Rule is what?
Sum of digits is multiple of 3 - last two digits multiple of 4.
3-4-5 - 5-12-13 - 9-12-15

42. Set Problems formula
(x-n(n)y-n)
Sum of digits is multiple of 9
s Sq. rt (x^r)
22

43. (1/4)^2
y2 - y1 / x2 - x1
Sum of digits is multiple of 3 - last two digits multiple of 4.
1/16
Figure out the probability for each individual event. Multiply the individual probabilities together.

44. Compound interest rule
Find simple interest then look for the answer that is a little bigger
P(E) + P(F) - P(E and F)
market value
Balancing

45. The number of outcomes that result in A divided by the total number of possible outcomes.
Any multiplication involving an even number creates an even product.
The probability of event occurring is...
(n-1)!
The amount after deductions

46. 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
For a fixed distance - the average speed is inversely related to the amount of time required to make the trip.
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.
Any multiplication involving an even number creates an even product.

47. 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?
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.
0.15n + 0.08(5) = 0.1(n+5)
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.
Number is a multiple of 3 and 2

48. Gross Profit formula
1.4
Gross Profit = Selling Price - Cost
2 steps
(x-n(n)y-n)

49. The average of 5 numbers is 2. After one number is deleted - the new average is -3. What number was deleted?
Immediately try factoring/simplifying when possible
22
16.6%
(n-1)!

50. Formula for area of a Trapezoid
1.7
(sum of bases)(height) / 2
sum = (average)(number of terms)
Balancing