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Flashcards in Math Deck (32)
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1
Q

isosceles

A

triangle with two sides of equal length

2
Q

normal distribution

A
  • 3 standard deviations (in both directions) is approx. 99%
  • The approximate percentages per standard deviation are: 34%, 14%, 2%
  • In a normal distribution: mean = median = mode = the center of the bell curve
3
Q

Combinations Formula

A

For “r” objects from a set of “n” objects:

nCr = n! / r!(n-r)!

4
Q

Probability Formula

A

Probability of an Event = Number of Favorable Outcomes / Total Number of Possible Outcomes

(The probability of multiple events will be the total of the probability of individual events multiplied together)

5
Q

Permutation Formula

A

(Order matters with permutations)

The number of permutations (nPk) of k objects from a set of n is:

nPk = n! / (n-k)!

6
Q

Median

A

The middle value in a set of values arranged from lowest to highest. (Note that if there is an even number of values, the median is then the mean of the two middle values)

7
Q

arithmetic mean

A

the average

8
Q

Mode

A

the number in a set that occurs most often

9
Q

Range

A

the difference between the highest number and the lowest number in a set

10
Q

Formula for 2 Overlapping Groups

A

Total = Group 1 + Group 2 + Neither - Both

or: T = G1 + G2 + N - B

(Note: the key words are NEITHER and BOTH)

11
Q

Ratios for 90o- 45o- 45o Triangle

A
12
Q

Ratios for 90o - 60o - 30o Triangle

A
13
Q

Integer

A

a “whole” number that does not contain decimals, fractions, or radicals;

can be positive, negative, or zero

14
Q

Positive

A

greater than zero

15
Q

Negative

A

less than zero

16
Q

Divisible

A

When a number divides into another number with no remainder

17
Q

Remainder

A

the “leftovers” of a division when one number doesn’t divide exactly into another number

18
Q

Divisor

A

a number that divides into another number

19
Q

Prime

A

a number that is only divisible by itself and 1;

(1 is not a prime number;

negative numbers and zero are not prime)

20
Q

Consecutive

A

in a row, usually ascending

21
Q

A Number is Divisible

by 3 if:

A

Its digits add up to a multiple of 3

22
Q

A Number is Divisible

by 4 if:

A

Its last two digits are divisible by 4

23
Q

A Number is Divisible

by 6 if:

A

It is divisible by 2 and by 3 (i.e. it is both even and divisible by 3)

24
Q

A Number is Divisible

by 8 if:

A

Its last three digits are divisible by 8

25
Q

A Number is Divisible

by 9 if:

A

Its digits add up to a multiple of 9

26
Q

A Number is Divisible

by 12 if:

A

Apply the rules of 3 and 4

27
Q

A number raised to power zero

A

n0 = 1

28
Q

Total interior angles of a polygon with n sides

A

Total interior angles = (n - 2)180

29
Q

Circle Relationships

A

θ / 360 = arc / circumference = area sector / area circle

30
Q

Volume of a Cone

A

1/3*πr2h

31
Q

Volume of a Cylinder

A

πr2h

32
Q

Diagonal of a rectangular prism (or cube)

A

d2 = a2 + b2 + c2