MATH 2030 3.0AF (Elementary Probability)
Assignments - Fall 2007

Assignments and their solutions will be posted here as they become available.

Access to the assignment solution pages has now been withdrawn.

If you took this course and now need access to those pages, feel free to contact me.

Section 4.2, numbers 5, 6
Section 5.1, numbers 1, 4a, 7
Section 5.2, numbers 1, 3a and then find both marginal densities and decide if X and Y are independent, 4bcd, 5, 9a, 11

Solutions. Questions graded: all.

Solutions. Questions graded: 8 (all but the third one)

Solutions. Questions graded: 8 (all but the last one)

Section 4.1, numbers 2a, 3ab, 12c
Section 4.4, numbers 3, 10ad. In problem 3, I want you to find the cdf first, and then compute the density. In problem 10, I want you to relate the cdf of the given random variable to the cdf of the standard normal distribution, and then take derivatives.
Section 4.5, numbers 2a, 6ab
Section 4 (review), number 4ac

Solutions. Questions graded: 8 (all)

This is practice for the midterm, to be completed by Wednesday, October 3, 2007 but not handed in

Section 1.5, numbers 3, 6ac
The Monty Hall problem: You are playing a game show, in which there are prizes behind three doors. One prize is good (eg a car), and the others aren't (eg. a goat and a rabbit). Once you pick a door, the host will open one of the other doors, showing you a bad prize. And he will ask you if you want to switch your choice. Should you?
The argument against is that since he always opens a door, he hasn't really given you any information that would favour one door over the other. So both remaining doors are equally likely to be correct (conditional prob 1/2 each), and there is no point in switching. The argument for switching is that you have no new information about your original choice. So the probability you picked correctly in the first place is unchanged at 1/3, and the (conditional) probability the other door is correct is now 2/3. Which is right?

Solutions. Questions graded: 7 (all but 3rd and 9th).

Solutions. Questions graded: 9 (all but 1st, 9th, 11th).