Kī o rahi tournament

Kī o rahi tournament

Pencil and paper
Overview
Using this Resource
Connecting to the Curriculum
Marking Student Responses
Working with Students
Further Resources
This task is about using a tree diagram to work out the probability of something.

In a kī o rahi tournament, the probability of a game ending in a draw is 1/3.
 

 

a)
After 48 games, what number of games would you expect to end in a draw?
 
__________
 
b)
 
What is the probability of a team drawing their first two games in the tournament?
 
__________
 
c)
 
What is the probability that a team does not have a draw in either of their first two games?
 
__________
 
d)
 
If a team played three games, what is the probability that their only draw was in the third game?
 
__________
Task administration: 
This task is completed with pencil and paper only.
Level:
5
Curriculum info: 
Description of task: 
Students interpret information presented in a tree diagram to calculate the probability of various events.
Learning Progression Frameworks
This resource can provide evidence of learning associated with within the Mathematics Learning Progressions Frameworks.
Read more about the Learning Progressions Frameworks.
Answers/responses: 
  Y10 (10/1998)
a) 16 moderate
b) or 0.11 or equivalent probability, ratio, or percentage. difficult
c) or 0.44 or equivalent probability, ratio, or percentage. difficult
d) or 0.148 or equivalent probability, ratio, or percentage. very difficult
Diagnostic and formative information: 
  Common error Likely calculation Likely reason
a)   Gives fraction rather than number.
b)

c)

d)


1 or
1 or
+
+
+ +
Adding rather than multiplying probabilities.
b)

c)

d)



+ =
+ =
+ + =
Adding rather than multiplying probabilities and incorrect addition algorithm.
b)

c)

d)



Probability (Draw)

Probability (Not a Draw)

Probability (Draw)

Quotes only the last probability in a sequence of events.