MATHEMATICS Block Diagrams and Dot Plots. Lesson Objectives The aim of this powerpoint is to help...

MATHEMATICSBlock Diagrams and Dot Plots

Lesson Objectives

•The aim of this powerpoint is to help you…

• to learn how to produce, read and interpret block diagrams

• to learn how to produce, read and interpret dot plots

Block Diagrams

• The data (discrete or categoric) is usually labelled along the bottom.

• One block represents one item or person.

• Block diagrams are the predecessors to bar charts but each block is individually visible within each column.

Block Diagrams - Example

• Class 2P visit a farm.

• When they get back from their visit, their teacher asks them which animal, out of all those seen at the farm during their visit, was their favourite.

• These are the results:

• The pupils draw a block diagram to show this.

Cow Dog Goat Hen Horse Sheep

6 10 2 4 7 1

Block Diagrams - Example

Cow Dog Goat Hen Horse Sheep

Cow Dog Goat Hen Horse Sheep

6 10 2 4 7 1

Dot Plots

• Dot plots are associated with discrete data rather than categoric data.

• The numeric data is usually labelled along the bottom.

• One large filled circle represents one item or person.

• Take care to ensure all the circles are the same size.

Dot Plots - Example• Class 2P were asked how many pets they each had at

home. Their results were put in this dot plot.

0 1 2 3

Dot Plots - ExampleQ1. How many students

have 2 pets?[Hint: count dots in 2 column]

ANS: 7

Q2. How many students have fewer than 2 pets?[Hint: count the dots in the 0 and 1 columns]

ANS. 20

Q3. How many students are there in class 2P?[Hint: count ALL the dots]

ANS. 30

0 1 2 3

What next?• Print out and read through the notes called Data5.

• Work through page 6 ONLY of the MyMaths lesson called Introducing Data which can be found at:

• http://app.mymaths.co.uk/350-resource/introducing-data

• Work through the MyMaths lesson called DotPlots (ignoring the questions on averages and range) which can be found at:

• http://app.mymaths.co.uk/371-resource/dot-plots

• Now answer the two sets of tasks on the Data5 notes pages

• Further practice is available by working through the worksheet: Block1.xlsx

• Move on to the Data-6 powerpoint