Q1) 50 students are enrolled in Economics class. After first examination, a random Sample of 5 papers had the following grades: 60, 75, 80, 70, and 90.
a) Compute the standard error.
b) Find out 90% confidence interval for mean grade of all the students in the class.
c) What is the margin of error?
Q2) New brand of breakfast cereal is being market tested. 100 boxes of cereal were given to consumers to try. Consumers were asked whether they liked or disliked the cereal. You are given their responses below.
|
Response
|
Frequency
|
|
Liked
|
60
|
|
Disliked
|
40
|
|
|
100
|
a) What is the point estimate of the proportion of people who like cereal?
b) Create a 95% confidence interval for proportion of all consumers who will like the cereal.
c) Determine the margin of error for 95% confidence interval that you constructed in part b?