The staff commute to work in different ways 2/5 drive, 4/15 catch the bus and 1/3 cycle
2 answers:
You might be interested in
Answer:
a. 1479
Step-by-step explanation:
Previous concepts
A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".
The margin of error is the range of values below and above the sample statistic in a confidence interval.
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
estimated proportion
n represent the sample size
Me =0.02 or 2% points represent the margin of error
Solution to the problem
The population proportion have the following distribution
We need to find a critical value in order to estimate the sample size required. In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 95% of confidence, our significance level would be given by and
. And the critical value would be given by:
The confidence interval for the true proportion is given by the following formula:
Wher the margin of error is given by:
And we are interested in find n, solving for n we got:
And replacing the values that we have, we got:
And if we round up to th nearest integer we got that n=1479