Describe the data 4, 5, 5, 6, 6, 6, 7, 7, 8

Step by step

The question

Question: describe the data 4, 5, 5, 6, 6, 6, 7, 7, 8: its center, its spread and its shape.

1 Draw a dot plot

A number line from 4 to 8.

One dot for each number.

4 first.

And so on.

2 Find the center

There are 9 numbers.

We count in from both ends to the middle one: number 5.

On the dot plot, that is 6.

The median is the center.

3 Find the spread

The spread: biggest minus smallest.

8 minus 4 is 4.

4 Describe the shape

The tallest stack, the peak, is at 6.

One peak, at 6.

Both halves look the same: it is symmetric.

5 Check

Let's check: we count the dots.

9 dots for 9 numbers.

Every number is crossed out.

So the dot plot is right, and so is the answer!

Let's look back.

First: draw a dot plot.

Then: find the center.

Then: find the spread.

Then: describe the shape.

Last: check.