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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
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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