For exercise 14 given a binomial situation with n 5 p 08
Solution
6.
Note that P(more than x) = 1 - P(at most x).
Using a cumulative binomial distribution table or technology, matching
n = number of trials = 8
p = the probability of a success = 0.3
x = our critical value of successes = 7
Then the cumulative probability of P(at most x) from a table/technology is
P(at most 7 ) = 0.99993439
Thus, the probability of at least 8 successes is
P(more than 7 ) = 0.00006561 [answer]
9.
Note that the probability of x successes out of n trials is
P(n, x) = nCx p^x (1 - p)^(n - x)
where
n = number of trials = 9
p = the probability of a success = 0.5
x = the number of successes = 4
Thus, the probability is
P ( 4 ) = 0.24609375 [answer]
13.
Note that the probability of x successes out of n trials is
P(n, x) = nCx p^x (1 - p)^(n - x)
where
n = number of trials = 12
p = the probability of a success = 0.1
x = the number of successes = 0
Thus, the probability is
P ( 0 ) = 0.282429536 [answer]
15.
Note that P(at least x) = 1 - P(at most x - 1).
Using a cumulative binomial distribution table or technology, matching
n = number of trials = 12
p = the probability of a success = 0.1
x = our critical value of successes = 3
Then the cumulative probability of P(at most x - 1) from a table/technology is
P(at most 2 ) = 0.889130022
Thus, the probability of at least 3 successes is
P(at least 3 ) = 0.110869978 [answer]

