Multiply (or distribute) the exponent<span> outside the parenthesis with every </span>exponent<span>inside the parenthesis, remember that if there is no </span>exponent<span> shown, then the </span>exponent<span> is 1. Step 3: Apply the </span>Negative Exponent<span> Rule. </span>Negative exponents<span> in the numerator get moved to the denominator and become positive </span>exponents<span>.</span>
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 .
The margin of error is:
95% confidence level
So , z is the value of Z that has a pvalue of , so .
Assume that nothing is known about the percentage of passengers who prefer aisle seats.
This means that , which is when the largest sample size will be needed.
Within 3.5 percentage points of the true population percentage.