The price of flour

The price of flour

Auto-markingPencil and paperOnline interactive
Overview
Using this Resource
Connecting to the Curriculum
Marking Student Responses
Working with Students
Further Resources
This task is about working out cost and weight for bags of flour.
2kg bag of flour     1.5 kg bag of flour     half kilo bag of flour
 
 
Ngāhina is buying flour to make rēwena bread. 

Question 2Change answer

a)  What is the price for each of the following?
     i)  3 packets of 2 kg $

     ii) 4 packets of 1.5 kg $

Question 2Change answer

b)  How many kilograms (kg) are there in ...
     i)  4 packets of 1.5 kg? kg

     ii) 9 packets of 0.5 kg? kg
Task administration: 
This task can be completed with pencil and paper or online (with auto marking displayed to students).
Level:
3
Curriculum info: 
Maths, Number and Algebra, Number Strategies
Keywords: 
decimals, multiplication, division, money
Description of task: 
Students work out the cost and the weights of buying several bags of flour.
Curriculum Links: 
This resource can help to identify students' ability to apply additive or simple multiplicative ideas flexibly to combine or partition whole numbers to solve multiplication problems.
 
Learning Progression Frameworks
This resource can provide evidence of learning associated with
Multiplicative thinking, sets 4-5
within the Mathematics Learning Progressions Frameworks.
Read more about the Learning Progressions Frameworks.
Answers/responses: 
 

 

 Y6 (11/2003)
a) i)
ii)		 9.30
9.60		 easy
easy
b) i)
ii)		 6
4.5		 moderate
moderate
Diagnostic and formative information: 
 

Student response

Likely calculation

Likely misconception
a) i)
    ii)

a) i)
    ii)

3.10
2.40  

6.20
4.80 or 7.20

 3.10 × 1
2.40 × 1

3.10 × 2
2.40 × 2 or 2.40 × 3

Pricing For Incorrect Units
Gives price for a single bag of flour.
Gives price for incorrect number of bags of flour.

b) i)
    ii)

 
4.2
0.45

  

Decimal Misconceptions
Treats 4 × 0.5 as 0.2
Treats 9 × 0.5 as 0.45