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6.2 Types of data

6.2 Types of data

There are two types of data that involve numbers, discrete
data and continuous data.
Discrete data is data that can only have exact values. The
values are usually whole numbers, but can include fractions. Numbers of goals scored and numbers of
people are examples of discrete data.

Continuous data is data that can take any value in a range.
All data that is measured is continuous data. If you round the Heights of trees and masses of babies
measurements to the nearest whole number, the data is still are examples of continuous data.
continuous.

Worked example 6.2
Write down whether the data is discrete or continuous.
a the number of cars in a car park.
b the height of trees in a forest.
c the time it takes to run 100 m.

a Discrete The number of cars must be a whole number, so it is discrete data.
b Continuous Height is measured, so it is continuous data.
c Continuous Time is measured, so it is continuous data.

✦ Exercise 6.2

1 Write down whether each type of data is discrete or continuous.
a the number of fence posts in a garden b the length, in metres, of each car in a car park
c the weights of pineapples in a box d the number of pineapples in a box
e the number of chairs in a classroom f the heights of the students in a classroom
g the number of mobile phones sold one day h the time it takes to complete a crossword puzzle
i the waist sizes of trousers sold in a shop j the number of pairs of trousers sold in a shop

2 Dakarai is explaining how he carried out a survey.

I have asked 10 people the size of the shoes they wear. My
results are 6, 6 1 , 8, 9, 9 1 , 10 1 , 10, 7 1 , 8, 6 1 . This is
2 2 2 2 2
continuous data as the values aren’t whole numbers.

Is he correct? Explain your answer.
3 Harsha is explaining how she carried out a survey.

I have asked 10 people their ages. My results are 23, 25,
22, 18, 36, 42, 12, 15, 17, 20. This is discrete data as the
values are whole numbers.

Is she correct? Explain your answer.
6 Planning and collecting data 65