Random or not

The digital object L3655 Random or not: analyse numbers of jubes (1:1:1) has a machine that makes three different types of jubes. Each jube type is equally likely to be produced. The machine randomly generates packets containing 12 jubes.

Students generally expect the most common packet will contain four of each type but the results challenge students’ understanding of expected outcomes.

Demonstrate this object with student participation. Some hints can be found in Random or Not: Teacher Notes. Generate nine packets observing the maximum number of any one type of jube in each.

Nine packets of jubes with maximum number of jubes of one colour in each packet identified. Column graph of the information showing five as the most commonly occurring.

Screen grab from L3655 Random or not: analyse numbers of jubes (1:1:1).
Source: © Education Services Australia Ltd, 2011

Observe the variation in the packets and make a prediction based on this small sample. This is often inaccurate. Generate results from larger samples of 100 and 1000, leading to predictions more consistent with the quite surprising theoretical expectations.

This learning object is one in a series of 17 objects. The other objects are listed under Related Items which can be found in the Details section. Students can also use the machine to conduct their own investigations in L5835 Random or not: open investigations.

Curriculum links

Year 8: Explore the variation of means and proportions of random samples drawn from the same population

Year 7: Identify and investigate issues involving numerical data collected from primary and secondary sources

Year 8: Explore the practicalities and implications of obtaining data through sampling using a variety of investigative processes

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