Answer:
(22.0297, 23.3703)
Step-by-step explanation:
Given that an economist wants to estimate the mean per capita income (in thousands of dollars) for a major city in California.
Let X be per capita income (in thousands of dollars) for a major city in California.
Mean = 22.7
n = 183
Population std dev = 6.3
Since population std dev is known we can use Z critical value.
Std error =
Z critical =1.44
Marginof error = ±1.44*0.4657=0.6706
Confidence interval 85%
=
Answer:
Correct option: A. P=0.057
Step-by-step explanation:
<u>Binomial Distribution</u>
The binomial distribution fits the case of n independent events each one with a probability of success equal to p where k successes have been achieved.
The PMF (Probability Mass Function) of the binomial distribution is
Where
The individual probability that an electronic device does not function properly is p=0.1. We know n=10 devices have been bought and we want to compute the probability that 7 devices function properly. Please notice that this is not the value of k since p is the probability of failure. The correct value of k=10-7=3. The required probability is