One out of every eight calls to your housel is from a family member. You will record

Question:

One out of every eight calls to your housel is from a family member. You will record whether the next call is from a family member.
a. What do you consider a "success" in this story? What is its probability?
b. What do you consider a "failure" in this story? What is its probability?!
c. Why is this a Bernoulli situation? What is the parameter?
d. Define in words what X is in terms of this story. What values can take?
e. What is the probability that the next time the phone rings, it will be from a family member?
f. If the phone calls are independent, what is the probability the 3rd call today will be from a family member?
g. What is the mean of X?
h. What is the standard deviation of X?