MATH112 Demo Exam #2, Chapters 7-11
No Books, No Notes, No Friends. You have 1 hour to complete the exam. Show all
work for maximum credit. A 3x5 handwritten note card is allowed.
Assume the following data is for problems 1 - 3:
Data relating the price of cats to the price of mice (all data is fictional)
Price of Cats Price of Mice
$50 50c
$40 35c
$35 33c
$55 53c
$45 47c
1) Determine the above data’s correlation. How strong is it?
2) Plot the data on a scatter plot and determine if the relationship is remotely linear
(Why? Why not?) Anything special to note about the data?
3) Find the linear regression of the above data if applicable. If it is not applicable,
describe why not.
Assume the following data is for problems 4 - 6:
Data relating the average hours of sleep each night to the approximate annual income (all
data is fictional)
Hours of sleep Annual Income
7 40,000
7 70,000
8 50,000
10 0
9 40,000
4) Determine the above data’s correlation. How strong is it?
5) Plot the data on a scatter plot and determine if the relationship is remotely linear
(Why? Why not?) Anything special to note about the data?
6) Find the linear regression of the above data if applicable. If it is not applicable,
describe why not.
7) Describe a method which you could run a simulation to predict the average
number of times Timmy presses his snooze button each morning. Suppose that
each time his alarm clock goes off, he has a 70% chance of snoozing for another 8
minutes. Otherwise he wakes up immediately. What results does your simulation
provide?