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  • Early Years Foundation Stage

Reaction Timer Timer

Age 16 to 18
Challenge Level Yellow star
  • Problem
  • Getting Started
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The reaction timer problem introduces this interactivity which measures the amount of time taken to react to a shape appearing on-screen:

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In this interactivity it is known that once a shape disappears an internal timer begins. The time until the appearance of the next shape is determined randomly through a clear, well-defined statistical process which is unknown to us. From the moment that this next shape disappears the timer resets and starts again; the random process then again determines the time until the appearence of the next shape. Familiarise yourself with the interactivity before considering this question:
  • Upon each shape disappearing there is a delay of a random length until the appearence of the next shape. How might you design an experiment to determine the nature of the random process giving rise to the delay?
Once you have designed the experiment, perform it and analyse the data. Can you produce a clear hypothesis as to the random process giving rise to the delay?

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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