Percentages and income tax

SubjectMathematics YearYear 8 CurriculumAC v8.4 Time115

Access denied

Please login or register to take this course.

Introduction

This set of resources provides opportunities for students to solve problems involving percentages, rates and proportions using technology (spreadsheets) in the context of income tax.

Australian Curriculum or Syllabus

Achievement standard

By the end of Year 8, students solve everyday problems involving rates, ratios and percentages. They describe index laws and apply them to whole numbers. They describe rational and irrational numbers. Students solve problems involving profit and loss. They make connections between expanding and factorising algebraic expressions. Students solve problems relating to the volume of prisms. They make sense of time duration in real applications. They identify conditions for the congruence of triangles and deduce the properties of quadrilaterals. Students model authentic situations with two-way tables and Venn diagrams. They choose appropriate language to describe events and experiments. They explain issues related to the collection of data and the effect of outliers on means and medians in that data.

Students use efficient mental and written strategies to carry out the four operations with integers. They simplify a variety of algebraic expressions. They solve linear equations and graph linear relationships on the Cartesian plane. Students convert between units of measurement for area and volume. They perform calculations to determine perimeter and area of parallelograms, rhombuses and kites. They name the features of circles and calculate the areas and circumferences of circles. Students determine the probabilities of complementary events and calculate the sum of probabilities.

Content descriptions

Solve problems involving the use of percentages, including percentage increases and decreases, with and without digital technologies (ACMNA187).

Solve a range of problems involving rates and ratios, with and without digital technologies (ACMNA188).

Teacher resources

In order to see the resources you must Register or Login if you already have an account.

 
Video

How does Australia's income tax system work?

 
Explainer

What is income tax?

 
Calculator

ATO’s simple tax calculator

Student learning resources

In order to see the resources you must Register or Login if you already have an account.

 
How to

Calculating income tax

 
Worksheet

Tax and tax rates

 
Investigation

Impact of income tax

Suggested activity sequence

This sequence is intended as a framework to be modified and adapted by teachers to suit the needs of a class group. If you assign this activity to a class, your students will be assigned all student resources on their 'My learning' page. You can also hand-pick the resources students are assigned by selecting individual resources when you add a work item to a class in 'My classes'.

Part A: What income tax

  1. Play the video How does Australia's income tax system work? as an introduction to Australia's progressive income tax system.
  2. Use a grouping strategy to organise students in groups of 3 or 4.
  3. Students read the explainer and in groups construct a brief definition of income tax and tax rates. Each group writes their definition on the board.
  4. When all definitions are displayed, discuss and refine the descriptions to come to a shared class understanding.

Part B: Calculating income tax

  1. Explicitly teach students how to calculate income tax. Use the Calculating income tax – How-to-sheet as a guide.
  2. Students complete the part 1 of the worksheet.

    Refer students to Calculating income tax - How-to-sheet to support them to complete the worksheet
  3. Review how to calculate averages. For example, the average rate of tax (ART). If income is $45,000 and total income tax is $4,288. ART = ($4,288 ÷ $45,000) x 100 = 9.53%.
  4. Revise how to calculate percentages, percentage increases and decreases. Use the Calculating percentage change – How-to-sheet as a guide.
  5. Students complete part 2 of the worksheet. (Note: students can do just a couple of the questions depending on the available time.)

    Refer students to Calculating percentages or ratios - How-to-sheet and Calculating percentage change - How-to-sheet to support them to complete the worksheet

Part C: Investigating income tax

  1. Walk students through the investigation instructions, reminding them of the similarities to the problem you modelled.
  2. Before students embark on their investigation, you may want to show them how to use ATO’s simple tax calculator. If necessary, refer to Using the simple tax calculator – How-to-sheet. This will enable students to focus on developing an understanding of progressive tax rather than getting bogged down in calculations.
  3. Students may benefit from working individually and/or in small discussion groups.
  4. Discuss student answers as a class.