Compare Data Displays Using Mean, Median and Range to Describe and Interpret Numerical Data Sets in Terms of Location (centre) and Spread (9)

Compare data displays using mean, median and range to describe and interpret numerical data sets in terms of location (centre) and spread(ACMSP283)

LO: To compare and describe data displays using mean, median and range for a set of data.

Know:

  • How to calculate the mean, median and range for a data set.

Understand:
That statistics can be utilised to compare and describe data sets in terms of location and spread.

Do:

  • I can compare and describe data displays using mean, median and range..

Visual Representations

Mean, Median and Range

Mean

Mean is also known as the average. The average shows you what the “typical” amount is.

To find the mean of a data set.

1) add all of the numbers
2) divide by the number of items in the data set.

Median

Median is also known as the middle. The median shows you what the middle number is that splits the data in half so that half the data is on one side and the other half is on the other.

To find the median of a data set.

1) arrange the numbers in order (ascending/descending doesn’t really matter)
2) find the middle number
3) if there are 2 middle numbers, you will have to find the middle between the two numbers.

Range

Range is the difference between the lowest (minimum) and highest (maximum) values.

Spread of Data

When you plot the graph of data, you can also interpret how spread out the data is.

The blue graph, shows that the data is very tightly bunched together so the spread of data is very tight or narrow.

The green graph, shows that the data is pretty evenly spread out so the spread of data is even.

The red graph, shows that the data is very spread apart so the spread of data is a wide spread.

The red graph shows that the data is not spread out and very tight.

The blue graph shows that the data is very spread out.

Interpreting Data Videos

Practise Questions

My Maths 9

Exercise 8A pg. 361 Q. 1-17

Exercise 8C pg. 373 Q. 1-6

Exercise 8D pg. 379 Q. 1-14

Exercise 8G pg. 397 Q. 1-15

My Maths 10/10A

Exercise 10A pg. 483 Q. 1-12

Next Lesson – Quartiles and Box Plots