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6 Planning and collecting data

What do you remember about planning and collecting data? Key words
Use the summary diagram, below, to remind yourself.
Make sure you learn and
What to think about understand these key words:
when collecting data
hypothesis
primary data
secondary data
data-collection sheet
equal class intervals
Decide whether to take data
from the whole population, or
from a sample (typically 10%
Should you
Decide how to collect your data.
of the population).
s ASK PEOPLE QUESTIONS
s CArry out an experIMENT
s record observations

What to think about
when displaying data

You can use a two-way table to
record discrete data. For
You can use frEQUENCY TABLES
example, this table shows which
wITH EQUAL CLASS INTERvals to
hand the students in a class use
gather continuous data.
to write. For example, this table
shows the mass of women
in a handball club.
Left Right Total
Girls
4 10
Boys 14
1 11 Mass, m (kg) Tally Frequency
Total 12
5 21 26 40 < m ≤ 50 /// 3
8
50 < m ≤ 60 //// ///
60 < m ≤ 70 //// /
6

In this unit you will learn more about collecting data. You will
design data-collection sheets, identify where and how to get data,
and use your data-collection sheets to collect real data.

6 Planning and collecting data 55