System Reliability, Probability, & Statistics

Question 0

Series Reliability

Answer 0

Joint probability: R(system) = R(1) * …R(n)

Question 1

Reliability

Answer 1

R(t) = e^-(lambda * t) R(t): reliability t: time lambda: failure rate; #failures / #time units during which items were exposed to failure

Question 2

Parallel Reliability

Answer 2

Inverse Joint Probability R(system) = 1 - (1 - R(1)) * (1 - R(2))…(1 - R(n))

Question 3

Z-Score

Answer 3

z = (x - mu) / sigma x: score mu: mean sigma: std dev

Question 4

Permutations

Answer 4

n! / (n - k)!

Question 5

Combinations

Answer 5

n! / k! * (n - r)!

Question 6

Mutual Exclusive Probability

Answer 6

Sum the probabilities of all the individual events.

Question 7

Probability of Independent Events

Answer 7

Multiply the probabilities.

Question 8

P “OR”

Answer 8

p(inclusive or) = p(X) + p(Y) - p(X)p(Y)

Question 9

Joint Probability (“AND”)

Answer 9

P = p(1) * p(2) * p(n)

Question 10

r

Answer 10

r = [S(xy) / (S(xx) * S(yy))]^(1/2)

Question 11

Poisson Distribution

Answer 11

P(r) = (((lambda * t)^r) * e^(-lambda * t)) / r!

t = time interval

lambda = average rate

r = given number of events

Question 12

TI-30XS Data and Formulae Editing

Answer 12

Data Entry Formulae Editing Statistics Computation

Question 13

MTBF

Answer 13

MTBF = 1 / lambda lambda: failure rate

Question 14

Fault Tree Analysis: p(top event)

Answer 14

Sum the cut set probabilities

Question 15

Boolean Logic Operators

Answer 15

+: OR •: AND