FRSC 4001 – Topics in Forensic Science II
Homework Assignment – Logic and Deductive Reasoning Exercises
Professor Bensley
Maximum of 10 Participation Points
As we have seen through examination of the literary character Sherlock Holmes, good logic and deductive reasoning skills are some of the hallmarks of a successful forensic scientist. Sometimes, a puzzle can be solved simply by slowing down, making excellent detailed observations, and logically putting two and two together to produce an answer of four. In the short story by Sir Arthur Conan
Doyle that you read, you were able to see multiple instances of Holmes putting these traits to action.
"You must not fear," said he soothingly, bending forward and patting her forearm. "We shall soon set matters right, I have no doubt. You have come in by train this morning, I see."
"You know me, then?"
"No, but I observe the second half of a return ticket in the palm of your left glove. You must have started early, and yet you had a good drive in a dog-cart, along heavy roads, before you reached the station."
The lady gave a violent start and stared in bewilderment at my companion.
"There is no mystery, my dear madam," said he, smiling." The left arm of your jacket is spattered with mud in no less than seven places. The marks are perfectly fresh. There is no vehicle save a dog-cart which throws up mud in that way,and then only when you sit on the left-hand side of the driver."
"Whatever your reasons may be, you are perfectly correct," said she. http://sherlock-holm.es/stories/pdf/a4/1-sided/spec.pdf
Your homework assignment is to use your powers of logic and deductive reasoning to solve the following puzzles. Good luck and have fun!
1. You’ve Got Character! (6 points – 1 per answer and 2 for the explanation)
Four students wrote book reports on the same book. Each student described the main character in his or her report. But their teacher could tell that these students didn’t read very carefully, because each one described the main character differently.

Annie wrote that name of the main character is Heathcliff and that he is short, has long hair, and wears an earring.

Bernard wrote that the name of the main character is Sherlock and that he is tall, has long hair, and wears an earring.

Carolyn wrote that the name of the main character is Romeo and that he is medium height, has short hair, and wears an earring.

Daniel wrote that the name of the main character is Harry and that he is short, has long hair, and never wears an earring.
Each student got only one detail of four correct. What is the correct description of the main character of the book? You MUST explain how you reached your conclusions to receive credit for your answers.
2. Three Little Pigs (5 points – 1 per answer and 2 for the explanation)
The three little pigs, as you know, built houses—one of straw, one of sticks, and one of bricks. By reading the six clues, figure out which pig built each house, the size of each house, and the town in which each house was located.
1.
Penny Pig did not build a brick house.
2.
The straw house was not medium sized.
3.
Peter’s house was made of sticks, and it was neither medium nor small.
4.
Patricia Pig built her house in Pleasantville.
5.
The house in Hillsdale was large.
6.
One house was in a town called Riverview.
Report your solution by listing the pig’s name, the size of the house that pig built, and the town in which that house was located. You MUST explain how you reached your conclusions to receive credit for your answers.

3. Who’s the Guilty Man? (4 points – 2 for your answer and 2 for the explanation)
On a distant island live three types of humans - Knights, Knaves and Normals. The Knights always tell the truth, the Knaves always lie, and the Normals sometimes lie and sometimes tell the truth.
Detectives questioned three inhabitants of the island - Al, Bob, and Clark - as part of the investigation of a terrible crime. The investigators knew that one of the three committed the crime, but did not at first know which one. They also knew that the criminal was a Knight, and that the other two were not. How they knew these things is not important for the solution. Additionally, the investigators made a transcript of the statements made by each of the three men.
What follows is that transcript:
Al: I am innocent.
Bob: That is true.
Clark: Bob is not a Normal.
After carefully and logically analyzing their information, the investigators positively identified the guilty man. Was it Al, Bob or Clark? You MUST explain how you reached your conclusions to receive credit for your answers.
This assignment is due at the start of next week’s class. No late submissions will be accepted.