Draw of socks

Draw of socks

Pencil and paperOnline interactive
Overview
Using this Resource
Connecting to the Curriculum
Marking Student Responses
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Further Resources
This task is about working out the probability as a fraction for a given outcome.

pairs-of-socks.png

Hana has six coloured socks in her drawer. Three socks are yellow and three are green.

Question

a)  Hana takes out one sock without looking.
     What is the probability it is green?

    • \(1 \over 6\)

    • \(1 \over 3\)

    • \(3 \over 6\)

    • \(3 \over 3\)

Question 2Change answer

b)  The first sock Hana pulled out was green.
     She puts this sock aside and pulls out another one without looking.
     What is the probability that this sock is also green?
Task administration: 
This task is completed with pencil and paper or online with NO automarking.
Level:
5
Curriculum info: 
Maths, Statistics, Probability
Keywords: 
probability, fractions, chance
Description of task: 
Students show understanding of probability by selecting a fraction to represent the colours of choosing an article of clothing from a drawer.
Learning Progression Frameworks
This resource can provide evidence of learning associated with
Interpreting statistical and chance situations, set 5
within the Mathematics Learning Progressions Frameworks.
Read more about the Learning Progressions Frameworks.
Answers/responses: 
 

Y10 (07/1998)
a) 3/6 very easy
b) 2/5 or 0.4 moderate
Diagnostic and formative information: 
   Common error Likely reason
b) 2/6 Forgets to subtract one from denominator.