How_To_Be_Good_At_Math

STATISTICS • THE MODE 279

The mode

The mode is the value that occurs most often in

a set of data. It is also called the modal value.

Sometimes a set of data has more than one mode.

3.8 m

3.8 m

3.7 m

3.7 m

2.8 m

2.8 m

4.4 m

4.4 m

2.8 m

2.8 m

Multiple modes

When there are two or

more values that are

equally common and

occur more often than

the other values, then

each of them is a mode.

Let’s see what happens

when we add an extra

giraffe, with a height of

4.4 m, to our group.

Extra giraffe

4.4 m

FIRST MODE

SECOND MODE

Let’s list the giraffes’

heights in order again,

from shortest to tallest:

2.8, 2.8, 3.7, 3.8, 4.4, 4.4

So, this group

of heights now

has two modes:

2.8 m and 4.4 m.

We can see from the list

that 2.8 and 4.4 both

occur twice, while the other

heights occur only once.

It’s easier to see the

most frequent value if

we put the heights in order,

from shortest to tallest:

2.8, 2.8, 3.7, 3.8, 4.4

We’ve worked out the

mean and median

heights of the giraffes.

Now let’s find the mode.

Then we look at the list of

heights to find the height

that occurs most often. This is

2.8, which occurs twice.

So, the mode of the

heights is 2.8 m. 0

4 m

3 m

5 m

2 m

HEIGHT

MODE

1 m

To find the mode, look for the value that

occurs most often. It often helps to

arrange the values in order.

278_279_Median_mode.indd 279 29/02/2016 18:06