The manipulated variable is the variable you are changing. Such as if your are doing a science experiment on if plants grow best using water,vinegar,or coke. The independent variable would be the plant because your using the same kind of plant within the experiment and the dependent variable would be the different liquids your using on the plant because this is the part of the experiment that your changing. Hope this helps!
A manipulated variable is an independent variable that has been manipulated to achieve a particular effect. A manipulated variable is at times referred to as an independent variable. Visit http://thelawdictionary.org/manipulated-variable/ for more information.