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Dependent Variable ?

Postby luma007 » Mon Nov 26, 2012 1:54 pm

Hello. My child is doing his science fair project on which disinfectant works best : natural vs chemical. He used slimy bologna on a cutting board and took samples of several disinfectants and observed which disinfectant had the fewest bacterial colonies on several petri dishes with agar. We know that the independent variable is the disinfectant, but what is his dependent variable? Thank you!

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Re: Dependent Variable ?

Postby klhjbh62604 » Mon Nov 26, 2012 4:25 pm

Hello luma007:

What a great project for a young student. Way to teach a child the need to clean surfaces.

You are correct in that the disinfectants are the independent variable.
The dependent variable represents the output - in this case it would be the slime of the bologna that would be on the cutting board. You are testing the disinfectants on their ability to clean the slime off the cutting board.

I hope this helps.

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Re: Dependent Variable ?

Postby luma007 » Tue Nov 27, 2012 10:14 am

Thank you so much for your response. Would it also be correct to say that the dependent variable is the number of bacterial colonies formed?

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Re: Dependent Variable ?

Postby drowningfish » Tue Nov 27, 2012 7:24 pm

Yes, it would be.

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Re: Dependent Variable ?

Postby KrishnaPatel » Sun Dec 23, 2012 4:32 pm

Just so you, and other people know, the dependent variable will always be what you measured in the experiment.

I hope his helps!
“Nobody important? Blimey, that’s amazing. You know that in nine hundred years of time and space and I’ve never met anybody who wasn’t important before.”
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Re: Dependent Variable ?

Postby murwarid3 » Tue Sep 24, 2013 5:51 am


Yes, just for a tip, the dependent variable is the results. Think of it as the dependent depends on the independent, the result.

Hope this helps!



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