More marbles

More marbles

Pencil and paper
Overview
Using this Resource
Connecting to the Curriculum
Marking Student Responses
Working with Students
Further Resources
This task is about fractions of quantities.
marbles
 
 
a)
The students in Room A lost \(1 \over 5\) of their 130 marbles in a game.
 
How many marbles did Room A lose? __________
 
 
b)
Room C had 366 marbles. They lost \(1 \over 6\) of these in a game.
 
How many marbles did Room C have left? __________
 
 
c)
Room E had 320 marbles. They won \(1 \over 8\) of the 288 marbles from another class.
 
How many marbles did Room E have now? __________
Task administration: 
This task is completed with pencil and paper only.
Level:
4
Curriculum info: 
Maths, Number and Algebra, Number Strategies
Keywords: 
fractions, fractions as operators, subtraction
Description of task: 
Students calculate fractions of a given number of marbles.
Curriculum Links: 
This resource can help to identify students' ability to apply additive or multiplicative strategies flexibly to find fractions of sets, shapes, and quantities.
 
Learning Progression Frameworks
This resource can provide evidence of learning associated with
Multiplicative thinking, sets 6-7
within the Mathematics Learning Progressions Frameworks.
Read more about the Learning Progressions Frameworks.
Answers/responses: 
 

Y7 (04/1997)

Y8 (04/1997)
a) 26 difficult moderate
b) 305 difficult difficult
c) 306 difficult difficult
Diagnostic and formative information: 
   Common errors Likely reason
a) 30 or 25 Student estimates rather than calculates.
b) 61
300		 The number of marbles lost.
Calculates 1/6 366 = 66 instead of 61.
c) 36
328		 The number of marbles gained.
Confuses rooms. Calculates 288 + 1/8 320.