Explanation:
Form a horizontal line as shown below (see attached image). This forms 2 separate smaller rectangles
The total area is therefore 32+9 = 41 cm^2
You can say "square cm" or "sq cm" in place of the "cm^2".
Answer:
a. The 95% confidence interval for the proportion of all adult Americans who would give themselves a grade of A or B on their financial knowledge of personal finance is (0.54, 0.588). This means that we are 95% sure that the true proportion of all adult Americans who would give themselves a grade of A or B on their financial knowledge of personal finance is between these two bounds.
b. Because this confidence interval is entirely above 0.5, the interval is consistent with the statement that a majority of adult Americans would give themselves a grade of A or B.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of , and a confidence level of
, we have the following confidence interval of proportions.
In which
z is the zscore that has a pvalue of .
Sample of 1,664 adult Americans, 939 people in the sample would have given themselves a grade of A or B in personal finance.
This means that
95% confidence level
So , z is the value of Z that has a pvalue of
, so
.
The lower limit of this interval is:
The upper limit of this interval is:
The 95% confidence interval for the proportion of all adult Americans who would give themselves a grade of A or B on their financial knowledge of personal finance is (0.54, 0.588). This means that we are 95% sure that the true proportion of all adult Americans who would give themselves a grade of A or B on their financial knowledge of personal finance is between these two bounds.
(b) Is the confidence interval from part (a) consistent with the statement that a majority of adult Americans would give themselves a grade of A or B?
Yes, because the confidence interval is entirely above 0.5.
Because this confidence interval is entirely above 0.5, the interval is consistent with the statement that a majority of adult Americans would give themselves a grade of A or B.
Answer: 0.82
Step-by-step explanation:
The probability of the computer not containing neither a virus nor a worm is expressed as P(∩
) , where P(
) is the probability that the event V doesn't happen and P(
) is the probability that the event W doesn't happen.
P()= 1-P(V) = 1-0.17 = 0.83
P()=1-P(W) = 1-0.05 = 0.95
Since and
aren't mutually exclusive events, then:
P(∪
) = P(
) + P(
) - P(
∩
)
Isolating the probability that interests us:
P(∩
)= P(
) + P(
) - P(
∪
)
Where P(∪
) = 1 - 0.04 = 0.96
Finally:
P(∩
) = 0.83 + 0.95 - 0.96 = 0.82