Mean Weight Change in Plants

A group of researchers conducted a study to analyze the weight of a specific type of plant over a period of time. The weights (in grams) of the plants measured at the beginning and after 6 months are as follows:

Initial Weights: 50, 55, 53, 52, 57

Weights After 6 Months: 65, 70, 68, 66, 72

To determine the overall change in weight, they calculated the mean weight for both the initial and final measurements. They then computed the difference between the two means. What is the value of this difference?