CS2104: Introduction to Problem Solving
Homework Assignment 10

Due at 8:00AM on Friday, October 28
40 Points

Here are the problems for Homework 10. You must provide a complete justification for your solutions.

Problem 1.

On Wednesday, May 5, 1976, the wicked Simon Legrew was murdered at his home in a Boston suburb. The police were able to place the time of death at between 11:10 and 11:30 PM. They arrested four suspects --- Jeeves, the butler; Fifi, the French maid; Julia, the cook; and Jessica, Mr. Legrew's private secretary. Under questioning, the four suspects made the following statements:

Jeeves:	I didn't do it. Jessica did it. Mr. Legrew was blackmailing Jessica. Fifi and I were watching television together from 10:10 PM until 12:30 AM.
Fifi:	I'm innocent. Jeeves and I were watching television together at the time of the murder. Jessica was being blackmailed. I saw Jessica speaking to Mr Legrew at 9:30 PM on the night of the murder.
Julia:	I'm innocent. Jessica was being blackmailed. Jeeves murdered Mr. Legrew. I saw Jessica leave the house at 10:00 PM.
Jessica:	I did not kill Mr. Legrew. I was not being blackmailed. I was in Chicago during the entire night of the murder. Fifi is the murderer.

Each of the four suspects made two true statements and told two lies.

Who killed Simon?

Problem 2.

Four men were asked about their yearly incomes. Their names were Earl, Moe, Luis, and Randy and their professions are architect, carpenter, plumber, and mason (not necessarily in that order). Each made two statements, but the only statements whose correctness can be depended on are those in which the speaker specifically mentions his own profession. Other statements may or may not be true.

Earl:	The plumber makes three times as much as the carpenter. The architect makes more money than I do.
Moe:	The carpenter makes more money than the plumber. Luis is either the mason or the architect.
Luis:	I make more than the architect. The carpenter makes less than each of the others.
Randy:	The plumber makes twice as much as the carpenter. I make more than the mason.

Match each person with his profession.