To find the total number of people who prefer the seaside or an island, you need to sum the preferences in the respective columns for each activity.
From the table provided:
- Seaside: 20 (Hiking) + 53 (Swimming) = 73
- Island: 12 (Hiking) + 40 (Swimming) = 52
Now, add the totals for the seaside and the island together:
73 (Seaside) + 52 (Island) = 125
Thus, the total number of people who prefer the seaside or an island is 125.