To estimate the median width of the oak trees based on the widths recorded from the 10 selected trees, we need to first sort the data in ascending order:
- The data set is: 63, 59, 12, 43, 71, 35, 28, 52, 47, 26.
- Sorting this data, we get: 12, 26, 28, 35, 43, 47, 52, 59, 63, 71.
The median is the middle value of a data set. Since there are 10 values (an even number), the median will be the average of the two middle numbers (the 5th and 6th values) in the sorted list.
The 5th value is 43, and the 6th value is 47.
Now, we find the average of these two values:
\[ \text{Median} = \frac{43 + 47}{2} = \frac{90}{2} = 45 \]
Thus, the estimated median width of all oak trees in the forest is:
45 cm