(Archived) Is there much of a difference between 99.9% or 99.999%?

2023-11-20 09:44:41

(Archived) Is there much of a difference between 99.9% or 99.999%?


Use our present need for cleanliness to engage your students. 

 

Does it really matter whether you kill 99.9% of the bacteria or 99.999% of the germs? In this activity, we've asked students to consider whether these claims about these two wipes' efficacy really make a difference.  We've supplied students with a list of bacteria counts on various surfaces and asked them to calculate how much of a difference these two different percents make in wiping out germs. Begin the activity with a notice and wonder while looking at the wipes.  Then show the kids the list of items without the number of bacteria and have them take some estimates as to which are most and least disgusting in terms of bacteria per square inch.  They will be surprised by some of the numbers! This is also an excellent opportunity to deal with repeating decimals.

For Adventurer members we have an editable Word docx, an Excel sheet with data and calculations, and solutions.


Activity Solutions & Supporting Materials
Share this:
Comments (1)
Alex - 2024-05-30 22:23:17
    Display 1 - 1 Of total 1
    It's Girl Scout cookie time again!
      Let your students talk about...
    Chocolate Milk and Mixture
    Image by FreepikChemistry experiments...
    2023 World Cup Cricket
    The Cricket World Cup is being played now (Octob...
    Spider-Man continues
    Spider-Man: No Way Home opened on December ...
    Giant Pumpkins 2022
    5 pound pumpkin compared to giant pumpkinLet your ...
    Cost of light bulbs - updated!
    There's a lot of misinformation out there ab...
    Spiraling squares - compass and straight edge
    Can you see the many spirals i...
    Mixing colors with food dye
    It's time to dye eggs! ...
    How should I cook my turkey?
    Should I oven bake it, deep fry it or barbec...
    Expensive Super Bowl ads
    Updated again for 2022! The team...