chapter 17 - probability Flashcards
1
Q
sample space
A
set of all possible outcomes
2
Q
event
A
subset of a sample space
3
Q
complementary probability - P(A’)
A
1-P(A)
4
Q
mutually exclusive - P(AUB)
A
can’t happen at the same time
P(A) + P(B)
5
Q
independence - P(A∩B)
A
do not effect each other
P(A) * P(B)
P(A U B ) = P(A) + P(B) - P(A∩B)
6
Q
mutually exclusive and independent
t
A
mutually exclusive events can’t be independent
7
Q
ΣP(X=x) =
A
1
8
Q
X ~B (n,p)
A
r.V. X = no. successes
n = no. trials
p = prob of success
9
Q
set notation for binomial distribution
A
X ~B (n,p)
q = 1-p = no. failures
10
Q
P(X = r)
A
nCr p^r q^n-r
11
Q
ΣP(X = r) =
A
1
12
Q
the required properties for binomial distribution
A
- has 2 mutually exclusive outcomes (success or failure)
- has a fixed number of INDEPENDANT trials = n
- prob of success at each trial is constant = p
13
Q
on calc do P(x>=1)
A
do 1 - P(x=0)
14
Q
nCr =
A
n! / r! (n-r)!
15
Q
probability of A when all outcomes are equally likely
A
n(A) / n(sample space)
