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Dilution Series Calculator

Age 14 to 16 Challenge Level:
 

This interactive diagram shows a dilution series made from four dilutions of an initial bacterial solution. At each stage of the dilution, a quantity of the culture is diluted with a quantity of the medium

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Try to calculate the dilution factor for various combinations of initial numbers. Can you create a general rule for the overall dilution? (Full screen version )
 

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Investigating the Dilution Series
 

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.
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