# Math 230 Assignments

### General remarks

1. Homework should be legible and neat, questions should be answered in order, and pages should be fastened with a staple with your name and student number on at least the front page in pen.

2. Homework will be collected on Thursdays in class and will cover the material through Tuesday's lecture (roughly). You should start attempting the problems as soon as possible after the material is presented in lecture. Please don't save it all for Wednesday night.

3. Solutions should be written carefully, using good English, complete sentences, and adequate detail, with citations from the book or notes. Some of these solutions may be explanatory proofs. A good guideline here is that you should write proofs the way you would like to see them in your textbook. In summary,  show all your working to get full marks.

4. Some of the textbook problems have hints in the back of the book. If you get stuck on a problem, you might find it helpful to look at a similar textbook problem that has a hint. These problems also make good practice problems.

#### Assignment 0, due never

Practice computations

Problems: Warm-up 1, Warm-up 2, Warm-up 3

#### Assignment 1, due Thursday September 15th

Covering Chapter 1: Word and numeric puzzles

Problems: 1, 2, 3, 4

#### Assignment 2, due Thursday September 22nd

Covering Chapter 2.1: Fractions and divisibility

Problems: 5, 6, 7, 8

#### Assignment 3, due Thursday September 29th

Covering Chapter 2.3: Prime numbers, greatest common divisor, least common multiple

Problems: 9, 10, 11, 12

#### Assignment 4, due Thursday October 13th

Covering Chapter 2.4: Modular arithmetic and properties of congruence

Problems: 13, 14, 15, 16

#### Assignment 5, due Thursday October 20th

Covering Chapter 2.4: Calculating a possible modulus and solving linear congruences

Problems: 17, 18, 19, 20

#### Assignment 6, due Thursday October 27th

Covering Chapter 2.5: Ciphers

Problems: 21, 22, 23, 24

#### Assignment 7, due Thursday November 10th

Covering Chapter 2.5: Codes

Problems: 25, 26, 27, 28

#### Assignment 8, due Thursday November 17th

Covering Chapter 5.4: Polyhedra and Euler's characteristic formula

Problems: 29, 30, 31, 32