Buying drinks

Buying drinks

Pencil and paperOnline interactive
Overview
Using this Resource
Connecting to the Curriculum
Marking Student Responses
Working with Students
Further Resources
This task is about reading information from graphs.
illustration: selection of different fizzy drinks
Four friends each bought a bottle of drink. The graph below shows the relationship between the cost of each bottle they bought and the volume in each bottle.
 
Cost and volume of different fizzy drinks
cost - volume graph of different bottles of fizzy drink

Question

a)  i)  Whose bottle held the least drink?

    • Courtenay

    • Marley

    • Grace

    • Troy

Question

ii)  Whose bottle cost the least?

    • Courtenay

    • Marley

    • Grace

    • Troy

Question

b)  i)  Who paid the least amount of money for the most amount of drink?

    • Courtenay

    • Marley

    • Grace

    • Troy

ii) Explain your answer
Task administration: 
This task is completed with pencil and paper or online with some auto-marking.
Copyright: 
Image: Maliz Ong | Public domain pictures | Public domain
Level:
4
Curriculum info: 
Maths, Number and Algebra, Patterns and relationships
Key Competencies: 
Thinking, Using language, symbols, and texts
Keywords: 
relationships, graph interpretation
Description of task: 
Students demonstrate their understanding of a graph showing the relationship between the cost of different bottles of drink and the amount each bottle contains. They then explain which bottle of drink is the best value for money paid.
Curriculum Links: 
Key competencies
This resource involves interpreting a graph in a novel way and explaining their reassoning. These relate to the Key Competencies: Thinking and Using language, symbols and text.
Learning Progression Frameworks
This resource can provide evidence of learning associated with
Patterns and relationships, sets 5-6
within the Mathematics Learning Progressions Frameworks.
Read more about the Learning Progressions Frameworks.
Answers/responses: 
  Y9 (02/2002)
 a)
i)
ii)
Courtenay's
Grace's
very easy
very easy
b)
i)
ii)
 Grace's

  • Grace has the lowest cost and gets a big volume (second best), and
  • Troy gets only a little more volume for a much higher cost, or
  • Troy's cost is high/too dear, or
  • Other completely correct statements showing a comparison between Grace and Troy.
  • Grace has the lowest cost and gets a big volume (second biggest), or
  • Other partly correct statements.

[Do not accept statements that Grace has the biggest volume.]
easy
very difficult
 
 
 
 
moderate
Diagnostic and formative information: 
  

Common error

Likely misconception

a)i)

Patrick

Confuses least volume and least cost.