SOLUTION: A recent study in NJ showed that 50% of all patients will return to the same dentist. Suppose
nine patients are selected at random, what is the probability that:
(a) Exactly five
Algebra ->
Probability-and-statistics
-> SOLUTION: A recent study in NJ showed that 50% of all patients will return to the same dentist. Suppose
nine patients are selected at random, what is the probability that:
(a) Exactly five
Log On
Question 627278: A recent study in NJ showed that 50% of all patients will return to the same dentist. Suppose
nine patients are selected at random, what is the probability that:
(a) Exactly five of the patients will return?
(b) All nine will return?
(c) At least eight will return?
(d) At least one will return?
(e) How many patients would be expected to return to the same dentist, i.e., what is the mean of
the distribution? Answer by ewatrrr(24785) (Show Source):
Hi,
Note: The probability of x successes in n trials is:
P = nCx* where p and q are the probabilities of success and failure respectively.
In this case p & q are = 1/2 or .5
nCx =
(a) Exactly five of the patients will return? 9C5(.5)^5(.5)^4
(b) All nine will return? 9C9(.5)^9
(c) At least eight will return? 1 - 9C9(.5)^9
(d) At least one will return? 9C0(.5)^0(.5^9) + 9C1(.5)^1(.5)^8
(e) How many patients would be expected to return to the same dentist, i.e., what is the mean of the distribution?
