A control is needed in a valid experiment because without controls then more then one variable is being tested. This can mess up the results.
To comare and contrast the differences and similarites.Im not really sure if this is right becuz i had the same question so ill see th votes in a few.Well wish me and u good luck cuz for me its due on monday
A valid experiment must include a control group for comparison, random assignment of participants to groups, manipulation of an independent variable, and measurement of a dependent variable to test the hypothesis.
He needed a control group. *Apex*
To be able to compare the results to something.
He needed a control group. *Apex*
To help you conclude that no uncontrolled factors significantly influenced your results. To help you determine that your experimental results are valid To help control for factors that aren't being tested but might affect results
to represent the population.at random. -apex (;
The treatments can be compared to each other instead of to a control
I.What types of plants were used in the experiment?II.What was the experiment's control? III.Was the experiment repeated more than once?
Draw a valid conclusion for that experiment.
A minimum of 6 sets of data are needed to make a valid conclusion.
A valid experiment is characterized by a clear hypothesis, a control group for comparison, random assignment of participants, and the ability to replicate the results. It should also have ethical considerations and controls in place to minimize bias and confounding variables.