Answer:
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
is the estimate
z is the zscore that has a pvalue of , also called the critical value.
The standard error is:
90% confidence level critical value
So , z is the value of Z that has a pvalue of
, so
.
Estimate:
72 petty theft cases and finds 45 of these have gone unsolved.
So
Standard error:
Answer: