Student Name:
Student Number:
Faculty of Science
FINAL EXAMINATION
Mathematics 203
Principles of Statistics I
Thursday, May 31st, 2007
2 p.m. – 5 p.m.
Answer directly on the test (use front and back if necessary).
Calculators are allowed.
One 8.5” x 11” twosided sheet of notes is allowed.
Language dictionaries are allowed.
There are 10 pages to this exam and 2 pages of tables.
The total number of marks for the exam is 100
Examiner: Dr. Jose Andres Correa
Associate Examiner: Professor David Wolfson
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Question 1
(4 points) A survey of residents of a particular community showed that 20%
were dissatisfied with the plumbing jobs done. Forty five percent of the complaints dealt
with plumber A. If plumber A does 40% of the jobs in the community, what is the
probability that a community resident will be dissatisfied with the plumbing job, given
that it was done by plumber A? (Show your work).
Question 2
(4 points) A die has two sides showing 1 dot each, two sides showing 4 dots
each, and two sides showing 9 dots each. Let X be the number that turns up when this die
is tossed once.
a) Find the probability distribution of X (make a table) (2 points).
b) Find the mean and the standard deviation of X (show your work) (2 points).
Question 3
(10 points) It is known that 30% of children in Quebec have a genetic
predisposition towards a condition which manifests itself as mild obesity in later life.
a) What is the probability that in a group of four Quebec children, no more than two of
them have this genetic predisposition? (2 points)
b) How large would such a group have to be in order that the probability of containing at
least one child with the genetic predisposition is at least 0.9? (4 points)
This is the end of the preview.
Sign up
to
access the rest of the document.
 Spring '08
 DrJoseCorrea
 Statistics, Standard Deviation

Click to edit the document details