A very surveyed 240 people about their favorite type of movie if 15% of the people chose documentaries how many of the people ch
2 answers:
You might be interested in
Answer:
The 95% confidence interval is
Step-by-step explanation:
From the question we are told that
The sample size is n = 48
The sample mean is
The standard deviation is
Now given that the confidence level is 95% , then the level of significance is mathematically represented as
Next we obtain the critical value of from the normal distribution table , the value is
The reason we are obtaining critical values of
instead of
is because
represents the area under the normal curve where the confidence level interval (
) did not cover which include both the left and right tail while
is just the area of one tail which what we required to calculate the margin of error
The margin of error is mathematically represented as
substituting values
The 95% confidence interval to estimate the mean breaking weight for this type cable is mathematically evaluated as
substituting values