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Challenge Level Yellow star
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Why do this problem ?

Conversion between, and use of, units is a critical skill in the sciences, and one which often leads to confusion. This problem will encourage students to understand the relationships between various types of units, as well as possibly introducing them to new important scientific units.It will also help to embed the important skill of checking numerical answers to see if they make sense in terms of orders of magnitude.

Possible approach

This question works well through discussion in pairs. Remind the students that common sense works well when dealing with units.

Key questions

In each case which is the small unit and which is the large unit?

Possible extension

Extension activities are given in the question. For a more challenging units question, try choose your units.

Possible support

Restrict the question to the parts using common units related to length.

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Choose Your Units

Which units would you choose best to fit these situations?

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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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