a An algorithm is a series of instructions or steps which when performed correctly will solve a problem in a finite time.

b Algorithms can be used to describe simple tasks or actions that you do each day.

c Algorithm description is commonly used in recipes, do-it-yourself manuals, and knitting manuals.

d Each step in the algorithm must be simple enough so that it can be easily carried out.

e For the algorithm to work in all situations, the steps must be performed in a particular sequence or order.

f Before an algorithm can be written, the problem must be fully understood.

g How you arrive at a solution depends very much on past experience.

h After the algorithm has been written it needs to be tested or checked.

i If the results are wrong it is modified or discarded.

j There is usually more than one correct algorithm.

2 An algorithm consists of a finite number of steps which, when followed, will solve a problem. An algorithm must have a definite start or beginning and a single end. The steps of an algorithm must be performed in a particular order for it to work.

3 Algorithms are created to solve problems. Algorithms provide a ‘recipe’ for solving the problem.

4 Algorithms can be used to solve most types of problem.

5 Algorithms are commonly found in recipe books, knitting patterns, do-it-yourself instructions, instruction books and instructions that come with systems such as automatic telephone systems.

6 The problem needs to be analysed and understood before an algorithm can be written to solve it.

7 The inputs and outputs affect how you arrive at a solution.

8 The algorithm needs to be tested after it has been written to make sure that it works properly. If it doesn’t work properly it will need to be changed and tested until it does work.

9

a get book

open to first page

read book

close book

b get bread

get butter

put bread in toaster

remove toast from toaster

butter toast

10 The algorithms will vary from student to student, but should include these basic steps:

get two slices of bread

get butter

get cheese

butter one side of each slice of bread

put cheese on buttered side of one slice of bread

put other slice of bread butter side down on cheese

cut sandwich

11

choose CD

take CD out of case

turn CD player on

put CD in CD player

press start button

listen to CD

when CD is finished, remove it from CD player

put CD back in case

turn off CD player

12

get bicycle pump

screw pump onto tyre valve

pump tyre up

unscrew pump from tyre valve

put pump away