## Dependent Variable ?

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### Dependent Variable ?

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!
luma007

Posts: 7
Joined: Mon Nov 26, 2012 1:04 pm
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Project Question: Hello. My son is doing his science fair project on "which disinfectants work best?" He added his own twist to it by comparing the effectiveness of natural disinfectants against chemical disinfectants. We know that the independent variable is the disinfectant being used, but what is the dependent variable? Thanks so much!
Project Due Date: 11/28/12
Project Status: I am finished with my experiment and analyzing the data

### Re: Dependent Variable ?

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.
klhjbh62604
klhjbh62604

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### Re: Dependent Variable ?

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?
luma007

Posts: 7
Joined: Mon Nov 26, 2012 1:04 pm
Occupation: parent
Project Question: Hello. My son is doing his science fair project on "which disinfectants work best?" He added his own twist to it by comparing the effectiveness of natural disinfectants against chemical disinfectants. We know that the independent variable is the disinfectant being used, but what is the dependent variable? Thanks so much!
Project Due Date: 11/28/12
Project Status: I am finished with my experiment and analyzing the data

### Re: Dependent Variable ?

Yes, it would be.
drowningfish
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### Re: Dependent Variable ?

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

I hope his helps!
Meg
“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.”
— The Eleventh Doctor
Megara7
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### Re: Dependent Variable ?

Hi,

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!

Thanks,

Murwarid
murwarid3

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Project Question: I would love to be involved in helping the young scientist community, by giving advice and encouragement to do their best. It's important for young kids to gain and seek knowledge by others, and I am willing to do serve as this role.
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