Answer:

To find the median, first, we need to arrange the app sizes in ascending order:

78, 97, 99, 100, 106, 109, 112, 114, 123, 129, 132, 134, 141, 145, 156

Since there are 15 data points, the median will be the middle value. In this case, the middle value is the 8th data point, which is 114.

Therefore, the median size of the apps is 114 MB.