Chapter 6

Question 1

expected value

Answer 1

the average value of a chance process, after repeating many, many trials

Question 2

E(X)=

Answer 2

sum of X*P(X)

Question 3

expected value is the same as…

Answer 3

mean

Question 4

st dev=

Answer 4

root of (sum of (X-mean)^2*P(X))

Question 5

+/- by an RV by a constant…

Answer 5

center (mean) +/- by that constant, spread (st dev) stays the same, shape stays the same

Question 6

x// an RV by a constant…

Answer 6

mean x// by the constant
st dev x// by the constant
variance x// by the constant
shape stays the same

Question 7

E(X+Y)=

Answer 7

E(X)+E(Y)

Question 8

st dev of X+Y

Answer 8

root of (st dev X^2+st dev Y^2)

Question 9

E(X-Y)

Answer 9

E(X)-E(Y)

Question 10

st dev of X-Y

Answer 10

root of (st dev X^2+st dev Y^2)