108 Unit 3 Problem solving: basic skills
B A rise in Danotian inflation would only
cause the fall in the ratio shown if the rise
in inflation in Wembling was smaller or
negative: we know nothing about this.
C If food prices rose less in Wembling than
in Danotia as a whole, this could explain
why the ratio fell – even if inflation in
Wembling was rising.
D Seasonal fluctuations would only manifest
themselves within a year, not between
years.
E Even if the inflation rate in Wembling is
falling, we know nothing about the inflation
rate in the whole of Danotia, so we cannot
conclude that the ratio would fall.Thus C is the only reasonable answer. The
others depend either on reading the graph
incorrectly or reading more into the graph
than we can safely conclude. This illustrates
the importance of reading and understanding
the information given (both verbal and in
other forms) and of reading the question
correctly. Beyond that, the deductions that
can be made follow from the application of
correct logic.
As in the previous chapter, solving these
two types of problem also depends on the
skill of recognising an identity between data
presented in two forms. As with the other
skills described here, this comes with practice
and it can be useful to look at data in
newspapers to see how they are presented
and to consider whether they are always
presented in the clearest way.
The next activity uses logic based more on
manipulating numbers. In this regard, it has
elements of the ‘finding methods of solution’
skill from Chapter 3.5. However, the nature of
the question places it closer to the ‘suggesting
hypotheses for variations’ category of questions.Commentary
Again we will look at these five answers in
turn. It is important to remember that the
graph represents the inflation in Wembling as
a percentage of the inflation in Danotia, not
the actual inflation rate in Wembling.A The graph represents only the ratio
between Wembling and the whole of
Danotia; high inflation in Danotia cannot
explain the shape of a graph of the ratio.The graph shows the inflation rate in the
province of Wembling as a percentage of
inflation in the country of Danotia as a whole
over the period from 2006 to 2012.2006 2007 2008 2009 201220112010100907080Wembling in ation as a percentageof Danotian in ationWhich of the following is the most plausible
explanation for the variations shown in the
graph?A Danotian inflation has been high over
the period shown.
B Danotian inflation has risen over the
period shown.
C Food prices in Wembling have risen
less than in Danotia as a whole.
D Food prices in Wembling are subject to
higher seasonal fluctuations than in
Danotia as a whole.
E The inflation rate in Wembling is falling
due to high unemployment.Activity