Farm helicopter

Farm helicopter

Auto-markingPencil and paperOnline interactive
Overview
Using this Resource
Connecting to the Curriculum
Marking Student Responses
Working with Students
Further Resources
This task is about the probability of a helicopter landing in an area.
diagram of three farms
A helicopter lands on one of three farms, drawn to scale above. It could be anywhere on this grid.

Question

a) What farm(s) is the helicopter least likely to have landed on?

    • Harris's farm

    • Tawanui's farm

    • Hurunui's farm

    •  Harris's or Hurunui's farm

    • It is just as likely to be on any farm.

Question

b)  What is the chance that it has landed on Tawanui's farm?

    • \(1 \over 10\)

    • \(1 \over 3\)

    • \(1 \over 4\)

    • \(3 \over 8\)

    • \(1 \over 2\)

Question

c)  What is the chance that it has landed on Harris's farm?

    • \(1 \over 15\)

    • \(1 \over 3\)

    • \(1 \over 4\)

    • \(3 \over 8\)

    • \(1 \over 2\)

Task administration: 
This task can be completed online and with pencil and paper.
Level:
4
Curriculum info: 
Maths, Statistics, Probability
Keywords: 
probability, equivalent fractions
Description of task: 
Students determine the probability of events related to a grid map.
Curriculum Links: 
This resource can be used to help to identify students' understanding of ordering outcomes and identifying likelihoods written as fractions.
Learning Progression Frameworks
This resource can provide evidence of learning associated with
Interpreting statistical and chance situations, sets 4-5
within the Mathematics Learning Progressions Frameworks.
Read more about the Learning Progressions Frameworks.
Answers/responses: 
 

Y8 (11/1997)
a) B (Tawanui's farm) easy
b) C ( 1⁄4) difficult
c) D (3⁄8) difficult
Diagnostic and formative information: 
  Common error Likely reason
b) B Treats each farm as equally likely, (rather than using the concept of area of a farm).
c) B Treats each farm as equally likely, (rather than using the concept of area of a farm).