A researcher compiled data on the weight (in kilograms) of two different groups of animals: Group X and Group Y. The weight data collected is as follows:
Group X: 15, 18, 22, 25, 30
Group Y: 20, 15, 25, 18, 30
From this data, the researcher calculated the mean and median weights for both groups. Determine which group's mean weight is greater than the median of the other group.