There were 29 days in February 1984.
Answer:
a) 0.23
b) The 95% confidence interval for the population proportion is (0.1717, 0.2883).
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
.
Point estimate
The point estimate is:

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 population proportion is (0.1717, 0.2883).
The answer is thirty two.
Answer:
f = -8
Step-by-step explanation:
7(f+3)+9=5(f-2)-3f
7f + 21 + 9 = 5f - 10 - 3f
7f + 30 = 2f - 10
5f = -40
f = -8