Cooking and preserving

Overview

Using this Resource

Connecting to the Curriculum

Marking Student Responses

Working with Students

Further Resources

This task is about multiplying with decimal numbers.

Question 1Change answer

a) Paula is pickling onions. She uses 0.5 litres of vinegar to pickle each kilogram of onions.

If she has 7 litres of vinegar, how many kilograms of onions can she pickle?

kilograms

b) Ashley Foods has 24 kilograms of vegetables to make into relish.

If 2 kilograms of vegetables need 0.75 kilograms of sugar,

how many kilograms of sugar will Ashley Foods need?

kilograms

c) Sam needs 450 grams of vegetables to make 1.25 litres of soup.

How many grams of vegetables does he need to make 0.6 litres of soup?

grams

Task administration:

This task can be completed on paper or online and has auto marking displayed to students.

Level:

Curriculum info:

Keywords:

Description of task:

Students use rates to solve word problems involving cooking and preserving.

Curriculum Links:

This resource can help to identify students' understanding of multiplying decimal numbers.

Learning Progression Frameworks

This resource can provide evidence of learning associated with

within the Mathematics Learning Progressions Frameworks.

Answers/responses:

Diagnostic and formative information:

	Common error	Likely calculation	Likely reason
a)	7.5 3.5	7 + .5 7 × .5	Wrong arithmetic operator chosen (should be 7 ÷ 0.5).
b)	18 16	24 × .75 24 × .75 - 2	Wrong choices of arithmetic operators.
c)	225 (or close)	0.5 × 450	Estimates the answer is approximately half of 450 rather than calculating it.