Answer:
4±√5
EXPLAINED ANSWER:
Since the variable is a binomial and it is squared, we apply square root on both side, and apply the ± sign on the right side (since the solution of a square root can be both positive and negative), and later pass the 4 positive to the other side.
√25 can be (5)(5) or (-5)(-5)
Answer:
n = 66.564
Step-by-step explanation:
Where:
z = confidence level score.
S = standard deviation.
E = error range.
2. We will find each of these three data and replace them in the formula.
"z" theoretically is a value that measures how many standard deviations an element has to the mean. For each confidence level there is an associated z value. In the question, this level is 99%, which is equivalent to a z value of 2.58. To find this figure it is not necessary to follow any mathematical procedure, it is enough to make use of a z-score table, which shows the values for any confidence interval.
The standard deviation is already provided by the question, it is S = 100.
Finally, "E" is the acceptable limit of sampling error. In the example, we can find this data. Let us note that in the end it says that the director wishes to estimate the mean number of admissions to within 1 admission, this means that she is willing to tolerate a miscalculation of just 1 admission.
Once this data is identified, we replace in the formula:
3. The corresponding mathematical operations are developed:
n= 66.564