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Item CV023005: In an experiment involving two variables (X and Y) that could affect the outcome of the experiment, changing X and keeping Y constant allows you to find out the effect of X on the outcome of the experiment.

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A student thinks that there are two variables (X and Y) that may affect the result of her experiment.

She decides to change only variable X and let variable Y stay the same.

What can the student find out about the effects of variables X and Y?

  1. If variable X affects the result of her experiment.
  2. If variable Y affects the result of her experiment.
  3. If both variables X and Y affect the result of her experiment.
  4. She cannot find out if either variable X or variable Y affects the result of her experiment.

Distribution of Responses

Chart showing distrubtion of responses for Item CV023005

Percent of students responding correctly

Overall50%
Grades 6–842%
Grades 9–1260%
Male52%
Female48%
Primary Language is English51%
Primary Language is not English39%

View data table