The Economics Network

Improving economics teaching and learning for over 20 years

Percentages: Books, Wastewater, Chickens and Elections (14'37")
This film shows how percentages are useful in a succession of situations: designing a robust wastewater treatment plant, working out the value of discounts in a book shop, voting margins in an election and rating the return on investment on machinery in a chicken processing plant.

Watch on YouTube | Download (643 MB)


  • Kurt Keilback: Water Quality Analyst, City of Boulder WWTP

The DeSTRESS films are presented by Ken Heather of the University of Portsmouth and produced by StreamLearn LLC. Published online in 2011

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