though there are differences in the table presentation, it can be seen that these students already figured out the relationship between the variables and can operate to control them.they controlled it by increasing one car, then decreasing 2 bikes or they decreased 1 car, and then increased 2 bikes, or they increased 1 car and increased 2 wheels, and decreased 1 car will decrease 2 wheels.they found out the combination of the correct answers according to this rule