Page 105 - Mathematics Coursebook

7.1 Simplifying fractions
10 Averages

Key words
average
height Make sure you learn and
understand these key words:
statistic

You o!en hear people talking about ‘average height’, ‘average average
income’, ‘average mass’ and ‘average age’, but what do they mean? mode
What other examples can you think of? median
mean
You may even hear about an ‘average’ family with 2.6 children. modal
What does that mean? How can you have 0.6 of a child? range
You need to remember that an average may not actually be a real class
value. It is just a number, calculated from real data, and is used to interval
represent a typical value for the data. frequency

"ere are several ways to work out an average. Deciding which frequency table
method to use can depend on the data you have. Sometimes modal class
the values are very close together, and sometimes they are very
spread out.

"e heights of one group are very similar. "e heights of the other

group are very varied.
In this unit, you will look at three kinds of average. You will also
learn how to measure how spread out the data values are.

104 10 Averages