Square spinner

Square spinner

Pencil and paper
Overview
Using this Resource
Connecting to the Curriculum
Marking Student Responses
Working with Students
Further Resources
This task is about investigating probability with a spinner.
Practical task: How to make a spinner
  • Carefully cut out the arrow, washer, and base from the card.
  • Make a hole through the centre of the arrow, shown by the , using a hole-punch.

 

  •   Make a hole through the centre of the washer, shown by the , using a hole-punch.

   

  •   Bend open one end of a paper clip so that it looks like this:

   

  • Push the unfolded end of the paper clip through the base at its centre. Thread the washer and then the arrow onto the paper clip.
  • Now fold the sharp end of the paper clip over so that the arrow will not fall off.
  • Make sure the folded over end of the paper clip does not touch the arrow.

 

  • Tape the flat part of the paper clip onto the underside of the base of the spinner to hold it in place.
Base 
Washer
 
 
Arrow  
 
 
 
Practical Task  
a)  When you have made your spinner answer the following questions.
     i)  If the arrow on the spinner was spun 80 times,
         how many times would you expect it to point to the black area when it stops? (Circle one)
 
(A)   0-9         (B)   10-30         (C)   31-50         (D)   51-70         (E)   71-80
 
    ii)  Explain why you would predict this.
 
 
 
 
 
b) Carry out an investigation to test your prediction.
 
•   Draw a table in the box below so you can record your results in an organised way.
•   Give your table headings to show the results you are recording.
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
c)		  
Now use the spinner to test your prediction. Record your results in your table.
Task administration: 
Equipment
The template shapes photocopied on to light card; scissors; sellotape; paper clips.

Prior to this assessment activity each student will need to make a spinner by following the instructions. Students may need help making a centred hole in the middle of the arrow. Alternatively, teachers could do this ahead of time to avoid any problems.

Level:
3
Curriculum info: 
Maths, Statistics, Probability
Keywords: 
probability, table construction, prediction, experiments, spinners, practical
Description of task: 
Students construct a spinner and use it to investigate predictions of the probability of outcomes. Findings are recorded in a student designed table.
Curriculum Links: 
This resource can be used to provide one source of evidence for students' understanding of describing likelihoods of outcomes for simple situations involving chance by selecting appropriate qualitative terms.
Learning Progression Frameworks
This resource can provide evidence of learning associated with
Interpreting statistical and chance situations, sets 3-4
within the Mathematics Learning Progressions Frameworks.
Read more about the Learning Progressions Frameworks.
Answers/responses: 

a)

i)

B
 

ii)

The chance/probability of the arrow landing on the black region is 1/4, one in four, 25%.

b)

  

Any 1 of:

  • A system for recording the frequency of the arrow landing on the black region or the non-black regions is drawn up, e.g., the headings "Black" and "Not Black" are recorded.
  • A system for recording the number of spins along with the number of times the arrow stops on black is drawn up, e.g., the headings "Number of spins" and "Number of times the arrow stops on black" are recorded.

c)

   •   Results are recorded using correct tally format including
     grouping tally marks into fives, e.g., .
   

The results show the arrow was spun 80 times, e.g., there are a total of 80 tally marks on the chart.
Diagnostic and formative information: 

 

 

Next steps: 
Extension
  1. As a class investigate the greatest and the least number of times that the arrow landed on black when spun for all members of the class.
  2. Record the results for the whole class.
  3. Get the students to draw a graph (bar or stem-and-leaf) showing the class results.