Answer:
0.8213
Step-by-step explanation:
-This is a binomial probability problem given by the function:
Given that n=21 and p=0.2, the probability that she experience a delay on at least 3 days is calculated as:
Hence, the probability that she experience delay on at least 3 days is 0.8213
5 is the in its value bc its on the y intercept meaning the starting point
1650 - 1200 = 450
What percent is 450 of 1200?
y = 450/1200
y = 0.375
37.5% increase
Answer:
The sample size needed is 2401.
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 .
The margin of error of the interval is:
95% confidence level
So , z is the value of Z that has a pvalue of , so .
Estimate the sample size needed if no estimate of p is available so that the confidence interval will have a margin of error of 0.02.
We have to find n, for which M = 0.02.
There is no estimate of p available, so we use
The sample size needed is 2401.