Mass Lab Station #1

In this lab station we were supposed to put some fiber into a beaker and weigh it. My claim to the question is I didn't think there would be a mass change because your no taking anything out of the system so the mass should remain the same. My evidence to my claim was the graph that was presented because there were few people who had a change in mas but the majority of the people had no change. My reasoning for my evidence is statistics because few people had a change in mass so the numbers cant lie. Another reason to support my evidence is if nothing is being added to the system then the mass shouldn't change but if something is added to the system then the mass should change.