Vector performed an experiment at a local farm to determine if the addition of bananas to his biomass cow manure recipes helps produce more or less energy. He collected random samples of manure and bananas from the farm, prepared 15 bottles of each of both mixtures, and placed a balloon on top of each bottle. After two weeks he measured the circumference of each ballon in centimeters; the bigger the balloon grew, the more energy that was produced. The results of the experiment are displayed in the box plots below.
What can Vector report to his local Biogas Club about the results of his experiments?