* In a scientific experiment, the temperature was the control variable, while the amount of fertilizer was the independent variable. (This explains the role of a control variable in an experiment)
* By keeping the speed of the car constant, we were able to isolate the effect of the tire pressure on fuel efficiency - speed was our control variable. (This shows how a control variable helps isolate the effect of another variable)
* Programmers use control variables in loops to determine how many times the loop should run. (This highlights a practical application of control variables in coding)
Remember that a control variable is a factor that is kept constant during an experiment to ensure that the results are due to the manipulation of the independent variable.