Thinking Skills: Critical Thinking and Problem Solving

3.7 Recognising patterns 105

played? (Hint: you first need to decide

which games have already been played, so

you know what is left.)

A B C D E

Britons 5 3 5 5 2

Danes 5 4 7 5 5

Normans 3 4 3 4 6

Saxons 2 4 1 1 2

4    The graph shows the charges made by

a printing company for making various

numbers of posters.

1234567

0

50

100

150

200

250

Number of posters

Total cost ($)

Which of the following pricing structures

would give the graph shown?

A $30 per poster

B $50 set-up charge + $20 per poster

C $40 per poster for the first four, any

extra $20 each

D $30 set-up charge, $30 per poster

for the first four, any extra $20 each

Draw the graphs for the other price

structures.

Answers and comments are on page 319.

1    Look in newspapers (business pages are

often useful) or on the internet to find

examples of numerical data in various forms

(verbal, graphical, tabular). Express the data

in a different form. Consider which form

makes the data clearest to understand.

2    Four-digit personal identification numbers

(PINs) are used to withdraw cash from

banks’ machines using plastic cards. It

can be very difficult to remember your

personal number. I have a method of

remembering mine. It is the two numbers

of my birth date (i.e. the date in the month)

reversed, followed by the two digits of my

month of birth reversed (using a zero in

front if either is a single number so, for

example, May would be 05).

Which of the following could not be

my PIN?

A 3221 B 5060 C 1141

D 2121 E 1290

3    Four house teams play each other in a

school basketball league. The scoring

system gives three points for a win, one for

a draw and none for losing.

They all play each other once, and

the league table before the last round of

matches is as follows:

Played Won DrawnLostPoints

Britons 2 0 2 0 2

Danes 2 1 1 0 4

Normans 2 1 0 1 3

Saxons 2 0 1 1 1

Which of the following points columns are

possible after the last two matches are

End-of-chapter assignments