Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

GRE math review > math foundations > Flashcards

math foundations Flashcards

You may prefer our related Brainscape-certified flashcards:
GRE® Vocabulary flashcards GRE® Psychology flashcards
1
Q

an integer is divisible by 3 or 9 if….

A

its digits add up to a multiple of 3 or 9

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

an integer is divisible by 4 if…

A

its last two digits are a multiple of 4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

an integer is divisible by 6 if…

A

it is divisible by both 2 and 3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

odd+odd=

A

even

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

odd+even=

A

odd

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

even+even=

A

even

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

odd*even=

A

even

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

even*even=

A

even

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

odd*odd=

A

odd

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How do you find the GCF?

A

1) break down integers into their prime numbers

2) multiply the prime factors they have in common

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what are the first 10 prime numbers?

A

2, 3, 5, 7, 11, 13, 17, 19, 23, 29

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How do you find the Least Common Multiple (LCM)?

A

1) break integers into their prime numbers
2) write out each prime number the maximum number of times it appears in any of the factorizations
3) multiple those prime numbers together to get the LCM

ex: 6: (2)(3)
8: (2)(2)(2)
2: max 3 times; 3: max 1 time

so (2)(2)(2)(3)=24

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

2^2 * 2^3 =

A

2^5

you add exponents when multiplying two numbers with the same base

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

4^5 / 4^2 =

A

4^3

you subtract exponents when dividing two numbers with the same base

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

(3^2)^3 =

A

3^6

exponents raised to an exponent: multiply exponents together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

5^0 =

A

1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

raising a negative number to an even exponent produces a

A

positive result

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

raising a negative number to an odd exponent produces a

A

negative result

19
Q

raising an even number to any exponent produces an ___ number

A

even

20
Q

raising an odd number to any exponent produces an ___ number

A

odd

21
Q

every positive number has x number of square roots

A

x=2

one positive and one negative

22
Q

T/F: only like radicals can be added or subtracted from one another

A

True

23
Q

How do you multiply or divide one radical by the other?

A

1) multiple or divide the numbers outside the radical signs

2) multiple or divide the numbers inside the radical signs

24
Q

simplify sqrt(72)

A

sqrt(72)=sqrt(36)sqrt(2)

6sqrt(2)

25
Q

what is (2/3) / (1/6)

A

denominator gets flipped and multiplied

(2/3) * (6/1) = 4

26
Q

(3^2)*(5^2) =

A

to multiply two different bases but with the same power, multiply the bases together and raise to the power
15^2

27
Q

(6^6) / (6^5)

A

6

when bases are the same, you subtract numerator minus denominator

28
Q

speed=

A

distance / time

29
Q

time=

A

distance / speed

30
Q

distance=

A

speed*time

31
Q

What are the all important T equations?

A

1/T= 1/a + 1/b

T= ab / (a+b)

32
Q

you are reverse-FOILing (turning a polynomial back into 2 binomials). What do you do?

A

start by writing what you know (x)(x)
the product of the two missing terms will be the last term in the original polynomial (number without an x) ; and the sum of the two missing terms will be the coefficient of the second term of the polynomial (the one with the x)

33
Q

factor the difference of 9x^2 - 1

A

(3x + 1)(3x-1)

34
Q

factor the difference of a^2 + 2ab + b^2

A

(a+b)^2 or (a-b)^2

35
Q

solve this quadratic x^2- 3x + 2 = 0

A

(x-1)(x-2)

x= 1 or 2

36
Q

in a normal distribution, ____ percent of observations fall within one sd of the mean

A
  1. 6 percent

34. 3% on each side

37
Q

In a normal distribution, ____ percent of observations fall within 2 sds of the mean

A

94.6 percent

13 more percent more on each side after 1 sd is surpassed

38
Q

In a normal distribution, ____ percent of observations fall within 2 sds of the mean

A
  1. 8 percent

2. 6 percent more on each side after 2 sds are surpassed

39
Q

What is the combination formula for groups and subgroups?

A

n! / k! (n - k)!

40
Q

There are 7 kids participating in the spelling bee, and 4 get ribbons. Using the combination formula, how many different groups of finalists are there?

A

n! / k!(n - k)!
7! / 4!(3)!
(7 6 5) / (3 2 1)
35

41
Q

What is the equation representing the probability of A or B occurring?

A

P(A) + P(B) - P(A and B)

this corrects for redundant inclusion of both A and B occurring

42
Q

when choices or events occur one after the other and the choices are independent of one another, the total number of possibilities is the ____ of the number of options of each

A

product

43
Q

you use the combination formula n! / k! (n - k)! for (ordered / unordered) subgroups?

A

unordered!

these questions are often phrased as looking for “how many different groups”

44
Q

T/F: use the combination formula for permutation questions (aka questions where order matters)?

A

False: you multiply the number of different options by each other
ex: (7)(6)(5)..

usually phrased like “different arrangements” or “different ways of ordering”

GRE math review (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions